Very happy viperskin owner here. I didn't get along well with the AI thumb-hole, and the pistol grip is MUCH better for me. Haven't handled the AI version, but the new design of that "V2" rear viperskin is working out great with my rear-bag situation. I think its big improvement over the older design. So, in my opinion, the V2 back end rocks, and that option makes the viperskins better. Is it correct that the viperskins also allow you to mount "tacticool" rails (and a flush-cup option) on the fore-arm and the AI does not? Otherise, not much difference between them as far as I can tell. If the differences mentioned in this thread don't matter much to you, I say just go with whichever has the closest match to the color you want...