Then theres the japanese knifes, which are only sharpened on one side, very similar to the razor style however, not very good for years and years of sharpening.
This is imprecise. You're talking here about what are usually called "single-beveled" knives, which is one of the more traditional grinding systems for professional-grade Japanese knives. Most of the Japanese-made knives discussed around here are not like this; if Global makes knives like this, it's news to me, and I'd be fairly surprised, because I'd have thought they'd get murdered in that particular market.
Single-beveled knives are slightly concave on the back, and have a single steep bevel on the front. Sometimes that bevel is slightly curved (clamshelled, hamaguri), and occasionally a microbevel is added right down at the edge, but in general it's easiest to think of them as having a single flat bevel. You can sharpen these for many, many years, with great pleasure and effect. Indeed, it is normal in professional Japanese kitchens where these knives dominate to sharpen them daily. On the whole, knives like this have a tendency to chip and are fairly finicky and hard to learn really well; they are also very expensive, and pretty much all the good ones are handled in untreated wood with carbon-steel blades. They are unquestionably delicate by comparison to standard-issue Western-style knives.
Double-beveled knives, most of the made in Western styles (chef's knife, slicer, etc.), are a major business among Japanese knifemakers these days, and their products are currently kicking the tails of pretty much all comers. Early entrants were people like Global and Shun, which are second-rate mass-produced knives by high-end Japanese standards, but are by comparison to most Western-made knives (e.g. Wusthof, Henckels) light and inclined to take a superior edge. Now that people into knives know about all this, they're inclined to sneer at Global and Shun in favor of the immensely superior knives made by people like MAC, Masamoto, Aritsugu, Konosuke, etc. All of these are Japanese knives, and yet they are also all double-beveled.
That said, many people do choose to profile such knives asymmetrically, which has some advantages and some disadvantages. Whichever way you slice it, though, these knives are double-beveled: single-beveled knives are a different breed altogether, and you can't make one into the other without doing horrendous, catastrophic damage. A true chisel-edge, such as is seen on old-fashioned nakiri, is a double-bevel --- it just happens that one of the bevels is set at 0 degrees.
The business about the heel being sharp is just something you get used to, or don't. If you ding yourself on it regularly, you can always round it off; a fat finger-guard like on a Wusthof does indeed make sharpening trickier.
Normally speaking, the principal single-beveled knives are the usuba, yanagiba, deba, and takobiki, also kiritsuke. Almost all the rest -- gyuto, honesuke, garasuke, sujibiki, etc. -- are double-beveled and based on Western models. The nakiri is native Japanese but double-beveled, and the santoku is a hybrid, again double-beveled.
As I say, I've never heard of a single-beveled Global knife. The vast majority of the market for such knives is with people who do professional, fairly serious Japanese cuisine of one kind or another, and most of those folks buy from reliable mid-high-end "artisan" manufacturers, not mass-producers like the folks who make Global and Shun. Shun has tried to edge into this market, but principally, as it appears to me, by selling to Western hobbyists rather than professionals.
Hope that's helpful.