Japanese Chef Knife (JCK) is a wonderful site and they sell some wonderful knives. Koki, the owner, is very helpful, straight as a die, keeps his prices as low as possible, is excellent at resolving problems, and uses extremely reliable shippers. His knives almost always come quickly and duty free -- a further discount. Consider that a ringing endorsement.
I can also endorse two other forums where you'll be exposed to a broader range of advice -- and hopefully advice more tailored to your needs than the typical "I chose X and you should too"
Rockwell hardness (HRc) as well as other hardness numbers don't tell the whole story when it comes to taking or holding an edge, or to chip and ding resistance. All you need to know is that there are such things as "too low," and "too high" but other than that, the knife's individual characteristics are more important than the HRc number. You're looking for something between the high 50s (say 58 or higher) and the mid sixties (higher than 64 and you're looking at a very difficult knife to sharpen.
Sharpening is what it's all about. No matter how well a knife holds its edge it's going to get dull eventually. The best knife is no more than a simple system of bringing a sharp edge to a task.
When it comes to hard, Japanese steels unless you already use water stones, you're going to have to change your sharpening regimen. Oil stones are frustratingly slow with harder steel. I use oil stones (although not with oil), you can take my word on this. When you do your value for money consideration, figure in the cost of a decent set of stones. Norton makes a combination 220/1000, plus 4000/8000, plus flattening stone kit which can be found for around $125. Yes, I said flattening stone. Waterstones need a lot of maintenance.
Sharpening isn't the sexiest topic, though. One of the things that makes Japanese knives interesting are kinds of construction called san mai and worikami. Although slightly different from one another, basically they're a way of sandwiching a very hard steel core between soft steel sides. The soft sides protect the core against shock and dings. They also ease sharpening considerably, since most of the metal you remove is from the sides.
As a general rule, Japanese knives are made thinner and are edged at a more acute angle than European knives. As a result of their construction, Japanese knives are lighter than their European -- especially German pattern -- equivalents. They're also "keener." Japanese manufacturers have been far more willing to use exotic boutique steels for kitchen cutlery than the Europeans, and in result, produced some outstandingly good knives. However, that rule is changing as European manufacturers like Wusthof integrate Japanese design into their own lines. In fact, Henckels sells a very high end, expensive, Japanese style, made in Japan line using an exotic steel (MC66) called Twin Cermax. Wusthof Le Cordon Bleu are also worth a look.
One of the few advantages western manufacturers have over the Japanese is fit and finish. Even very high priced Japanese knives can be finished poorly to the point of needing some Dremel renovation by the new owner. Many of the Japanese manufacturers are essentially "Mom and Pop" operations and QC depends a lot on who's there at the time, how rushed they are, etc. Another area where the Japanese often fall down is handle design and size. Unfortunately, there's no place to try out the more exotic brands, you'll have to rely on internet wisdom and/or the experience of the retailer. Another aspect you may find surprising is that often Japanese knives are not well sharpened at the factory -- often leaving that to the customer. This can mean a little "touch up" or a complete re-profiling, and includes very expensive as well as mid and lower priced blades.
By all means check your choices with the posters on Fred's cutlery Forum -- a site pretty much dedicated to high-end Japanese kitchen cutlery. If it's sold at JCK, Korin, Epicurean Edge, or a few other of the popular retailers -- someone's at least tried it once.
Most American pros and serious amateurs think of MAC, Global and Shun when they think of Japanese knives. Since you're nosing around JCK you seem to be past those, but briefly:
Shuns are very good knives, very attractive, and by no means a bad value. The Classic series is designed for the Western market. It uses a "D handle" which means the knives are exclusively right or left handed -- which I consider a safety issue. The handle is something you'll either like or dislike right off the bat. They're san mai suminagashi which means the outer cladding looks like (but isn't) Damascus steel. The interior core is VG-10 which is a very good stainless steel formulated in Japan especially for knives. At this moment, Shuns are The Hot Knife for American chefs who aren't too deeply into knives. They're well enough merchandised that you should be able to find a store that will let you take one for a test drive. The suminagashi design is easily damaged. The knives are relatively easy to sharpen for a Japanese stainless knife (more difficult than a Wusthof, e.g., but you can use oil stones), and hold their edge failry well for a Japanese stainless knife (much better than any mass produced European). I don't care for them.
Globals are highly idiosyncratic, and also designed for the Western market. But Globals were designed with the professional chef in mind. The knife's handle design presupposes a pinch grip. Even with a pinch if you don't find it comfortable the first time you hold one, you never will. The knives are very light and incredibly well balanced. Five years ago Globals were The Hot Knife in the same way Shuns are now. It seems to me that nearly everyone who bought one during the height of their trendiness has moved on to other knives -- complaining of discomfort related to the grip or the feel of the spine under the index finger. Globals are also made of VG-10 but it isn't hardened quite as much as the Shun. Construction is a simple blade without cladding. Most knives are stamped, a few chef's are forged. Globals sharpen a little more easily than Shuns, but don't hold their edge particularly well. Although I admire the balance and weight, they do not fit my hand at all.
MAC is a brand you might want to reevaluate. The MAC Original and MAC Chef lines were also designed for professional cooks. Pros on a budget. They are ugly, no nonsense, low cost, high performing knives -- the best possible choice for a prep cook. Somewhere along the line, chefs with a little more money started fooling around with them and liked their weight and edge characteristics. Word got around to serious food amateurs, too. MAC introduced the Professional line for these wealthier, more demanding customers. They went with a slightly better steel, added a bolster-like ferrule for balance, and a more attractive handle. They take a killer edge, hold it well, and are relatively easy to sharpen. The 9" - 10" chefs are well balanced. Tons of value. I like them heap plenty much.
Now on to some of the brands (mostly from JCK) you found confusing.
Hiromoto Tenmi Jyaraku AS series: If I were buying a new Chef's knife, I'd either buy one of these or something a heck of a lot more expensive. They're an incredible value in the same way a Corvette is. High performance exotic, usable as a daily driver, priced far lower than anything comparable. They're everything you want in a Japanese knife. Simple design, with a little deep engraving kanji script. Warikomi with one of the most famous and high-end Japanese steels at its core -- Aogami Super. However, AS is not stainless. That means it will darken slightly compared to the cladding as the knife gets used. It also means a little more maintenance to guard against pitting, and to sharpen it out when it occurs. "Maintenance" mostly means frequent damp wipes, and regular rinses, followed by a quick towel dry. Not much trouble, but more trouble than a pure stainless blade. However, the payback is that aogami super sharpens far more easily than a similarly hard stainless (but you NEED waterstones), does not chip or ding nearly as easily, and holds an edge at least as well. Light, well balanced, agile, very sharp knives. Hiromoto fit and finish in the AS line is usually good. The handles usually fit well and are suitable for larger western hands. The factory edge, typically, requires some work out of the box. However once the edge is on, it's easily maintained by steeling -- a function of carbon steel's relative flexibility
Hattori HD: "Damascus" knives very similar to Shun Classic, except for the handles -- VG-10, etc. F&F isn't quite up to Shun standards, otherwise slightly better all around. The factory edge is better than decent. Harder to sharpen than a Shun, this is probably the line where waterstones become necessary. Hattoris holds an edge slightly better than Shuns. I've heard a few complaints about chipping on the net. If you must have a Damascus look, this is probably the best choice without spending beaucoup bucks.
Misono UX-10: Great knife if you can afford it. One of the best possible choices. Great steel. Consistently good F&F as Japanese knives go, with very comfortable handles. Stainless throughout, san-mai construction. Fairly hard to sharpen. Great edge retention. Excellent balance, light, agile, very sharp.
Ryusen Blazen and Ryusen Bu-ry-zen: The Blazens are sold at JCK, and the Bu-ry-zen which are a very slight improvement over the Blazens are sold at Epicurean Edge. Same review as .
Other Misonos: The F&F starts to fall off for the other stainless knives. Dollar for dollar, I'd take a Misono over a Shun, though. The Misono Swedish line is not stainless and has all the virtues and drawbacks of carbon steel. Too much trouble for most people. I like it. I especially like the dragon engraving on the big knife.
Kikuichi Elite Gold: Another VG-10 knife. Pretty darn good.
Kikuichi Elite: Excellent choice for a simple, all carbon knife. Good prices. Seriously consider these if you decide to go carbon. Very good F&F. Get very sharp. Stay very sharp. An easy knife to steel, as well.
Tojiro: The DPs are value leaders and a great first Japanese knife. It's a knife most users outgrow quickly, as soon as they realize the advantages of Japanese cutlery they want something better. The core is OK, but not great -- not as good as VG-10, e.g. A lot of people have major issues with Tojiro DP handles. Balance is an issue in the longer knives. Tojiro Stainless -- same knife with a hollow stainless handle. Tojior Damascus -- very good knife but not as good as the Hattori HD.
Ryusen Damascus: Same everything as the Hattori Damascus, in fact the blades are made on machines jointly owned by both companies according to a process set up by Ryusen. Ryusen assembly and F&F is not as good as Hattori's. My speculation is that's because the HD is Hattori's best "mass market" line, but not Ryusen's; and Ryusen reserves the most care for the Blazens.
Togiharu: I don't have any experience of my own with these -- and nothing's really stuck from someone I know well enough to really trust. However the manufacturer has a really good rep for value, especially at the entry-level. Above that, my impression is that the Inox line is more or less comparable to the Mac Professional and the G-1 line to the MAC ultimate. I'd go with the MAC for the guarantee.
Full Disclosure and Take it for What it's Worth: Nearly all my "working" knives are "vintage" or "antique" carbon steel Sabatiers -- Elephant, K or Elephant "Nogent." My go-to, a 10" chef's is K-Sabatier from the sixties. I sharpen with a Norton combination India, plus a Hall's soft Arkansas, and a Hall's surgical black Arkansas; and steel with a HandAmerican borosilicate glass "steel" and a Henckels extra-fine. While I love my knives, I wouldn't recommend them to someone without a particular interest in both carbon and European knives. (If you are interested, you can still buy very high quality French carbon knives from several sources.) The sharpening stones are appropriate for the knives and are used dry or with a very light spritz of water. The borosilicate "steel" is extremely fine and extremely good -- especially while the knife is still very sharp. After a fe weeks, the edge wears down a little I switch to the Henckels which, although "extra fine," is more deeply grooved than the glass and puts a little tooth on the edge. I get to six to eight weeks of heavy home use between sharpening -- that's about 8 days in restaurant years.
Hope this helps,