It depends on which rom your friend plays. If he plays set 1 or 2, then he’s right, those are the closest versions to the original MVS version. We had a little test here in SoCal at one of our meets, and each of us came up with our own opinions. Mine are: The PS2 version is good if you don’t want to get the Neo Geo version or play the rom, but, if you’re used to the timing on the Neo Geo, its best not to get used to the PS2. it took me a while to adjust to it, some of the links, cancels, breaks and feitns chains felt akward on the PS2 version. And that GC thing doesn’t bother me since you should be able to tell when someone does a GC.
A+B breaks certian specials with each character, everyone except Kain and Hoku have 1 move they can break.
You’re right on the A+B and d+A+B attacks, but you need to remember that some characters don’t leave the ground, and their overhead doesn’t get as much invin than other characters.