A few comments...
Jonathan Kaplan (OR)
>Japanese chisels in general are a bit different than their western coutnerparts, though still recognizably the same beasts.
First, Japanese chisels are made from two kinds of steel -- a very hard steel that makes up the cutting edge, and a backing of softer steel. There have been many discussions on this site about whether this matters, and if so how much, so I'll leave you to search for those threads if you are interested. (The idea is to get the benefits of hardness without the brittleness; how well this works is the subject of some debate...)
They tend to be a bit shorter than western-style chisels. Some peopel like that, some don't. The backs are hollowed rather than flat. This aids flatting, but can in time require some maintanence.
Some good sources for japanese chisels (in no particular order) are:
Hida Tools: http://www.hidatool.com/wood.html
Hiraide America: http://www.japanesetools.com
Japan Woodworker: http://japanwoodworker.com
Misugi Designs: http://www.misugidesigns.com/tools.html
And I'm sure there are others. I've mostly bought from Japan Woodworker and have had no complaints. Their selection of ultra-high-end tools is not as extensive as some of the other sites, but since I'm not really in the market for the ultra-high end, that hasn't proved to be a problem for me.
I think at some point the main issue with chisels -- bench, mortise, paring, or whatever -- has to be what fits your hands and work-style. There are a large number of high-quality chisels with great steel, etc., out there. I happen to like the feel (and I'll admit it, the look) of japanese chisels. But that's not to say that there aren't a number of other choices that might work better for you...
Best,
jk