Chris was right about the Masanobu not being san-mai, but rather "mono-steel." I stand by the rest of my critique though. It's thick (as wa-sujis go), heavy (because of the handle), expensive, and not particularly good -- or at least not for the price. Korin pushes them pretty hard, and they have something of a reputation among Korin's customers in Europe (where they are absolutely one of the very best sources for Japanese knives) and New York; but otherwise not so much.
That said, it's important to keep context in mind and some semblance of reality. It's still a very good knife. At these elevated prices, any knife better darn well be good. But enough with the fair and balanced. Let's go back to the whining, it's more fun.
Knife context is nothing without a discussion of edge qualities. They may be the be-all-end-all of knives, but if they aren't, nothing else is very close. It's easy for a reviewer (or me, for that matter) to make very nuanced distinctions, but not only do most people not sharpen well enough to ever tell the difference, you're taking my abilities on faith. Further, few of those who do maintain their knives, maintain them at such a consistently high level of performance that absolute edge taking abilities of high-end steel are tested in ordinary home use. So, how important is it really? I can't answer for you, but can only say it's of highest importance to me as I use knives, and report my experiences accordingly.
The Masanobu is made from a Takefu stainless alloy they call VG-10. VG-10 is a very good alloy and had something of a reputation as being THE wonder stainless. At least it was sold that way; and the gospel preached by a number of experts who should have known better. In fact, it's just one very good stainless among several others including VG-1, VG-5, a couple of the "Swedish" steels, ginsanko (aka G3), etc. Again, we return to absolute edge taking and holding abilities. VG-10, hardened to 59 is good stuff no doubt, but edge geometry counts for more.
Some VG-10 knives are quite prone to chipping -- Shun for instance. I believe Masanobu has that rep as well, but am not sure. I had lunch today with "KC," a guy who knows a LOT about knives, certainly more than me, we talked about Masanobus, and he was the one who brought that up. He also used the term "chunky."
The real difference though in a usable edge, providing you have the sharpening skills to exploit it, lies in geometry -- and that's where the lasers like Tadatsuna, Suisun Honyaki, Konosuke, etc., come in. Provided you can live with the thinness, they are just plain better. It's hard to talk about sharpness as an absolute, because the term can mean so many things, but, everything else remotely approaching equal, lasers certainly ACT sharper. That's just how thin is.
In my opinion the Hattori Forum Knives are excellent, and the yo-handled FH knives Chris pictured are as good as "yo" VG-10 gets. What Hattori knows that no one else does, I don't know. But it's something important.
I actually owned four Hiromoto AS knives -- two gyutos, a suji, and a petty. (AS means "Aogami Super," another wonder steel, but this time carbon. As Chris noted, the AS is sandwiched between layers of plain-jane soft stainless.) We bought them a few years ago with the idea of replacing my old Sabatier carbons which made up our "core set." The Hiromoto handles were short and narrow, nowhere near as good as our au carbones or Nogents, and neither my wife nor I cared for them. Their reputation for edge taking was overblown. Yes they got very sharp, but not any better than my carbon Sabatiers when both were sharpened to similar angles. While the Hiros did hold their edges longer, they were more prone to chipping and not as easy to maintain. (Like every other san-mai knife, they felt "damped" to me -- I'm not the only person who feels that way about san-mai -- KC, for instance, compares them to condoms -- but it's definitely a minority opinion and probably doesn't apply to you.) Moral of the story: We loved them so much we kept the Sabs and moved the Hiros along. A lot of people though, absolutely swear by Hiromoto AS. Who's to say? It's all very individual. I just calls 'em as I sees 'em.
FWIW, we currently have four "slicers:" A 15cm SS Konosuke petty -- a "petty" is a 5" - 8" slicer-profile which gets used for a lot of things, and around here that includes a fair amount of trimming; a 6" Nogent slicer(carbon Sabatier), used in the same way; a 10" K-Sabatier au carbone; and a 30cm Konosuke HD, which at the moment, is my most frequently used knife for pretty much everything which isn't way too heavy duty.
I'm surprised that Chris doesn't use his slicer(s) that often. Maybe we just do more trimming, portioning and slicing 'round here.
One of the things which makes the Konosuke 30cm suji so versatile is its agility. Not only does it have a splendid profile, and a handle which suits me to a "t," its light weight (just a skosh over 4oz, compared to 7oz for a Masanobu 27cm) makes me less aware of its length than I would otherwise be. Another is how easy it is to make and keep sharp. Sharper than the factory edge -- which wasn't bad. These are qualities the Masanobu does not possess to anywhere the same degree. On the other hand, it does have a very pretty handle.
Edited by boar_d_laze - 7/21/11 at 9:16pm