I have a couple of different sets of chisels: Koyamaichi for dovetailing in very hard woods, Veritas PM-V11 and O1 (I was one of the testers for Lee Valley, hence ended up with both), vintage Stanley 750 (which is high carbon steel), and Blue Spruce in A2, which were the chisels that got me thinking about the bevel angle of bench chisels.
The point of bench chisels is that they are all rounders and more often used with a mallet (or gennou). They have to cope with impact, which places much stress on an edge. The short answer is that I bevel all my bench chisels at 30 degrees. You would not wish to use A2 steel below this with chisels, and Japanese white steel, which gets sharper than anything else, also needs to be 30 degrees .... so where is the advantage in going lower? Just keep your bench chisels sharp.
For paring I use Japanase slicks (Kiyohesa), which are at 25 degrees. But that is another story.
You may be interested in this article I wrote comparing the different steels in bench chisels:
http://www.inthewoodshop.com/ToolReviews/FourChiselSteelsCompared.htmlThe chisels used were the Veritas PM-V11, vintage (not the new versions) Stanley #750 (which is a HCS similar to O1, but I am unsure of the specific type), Koyamaichi white steel, and Blue Spruce A2.
Regards from Perth
Derek