One thing to think about with companies putting pistol grips or thumbhole stocks on thier shotgung...the grip changes, but the safety stays in the same spot. Make sure you can still easily/quickly flick the safety off with the grip you choose.
I ran into this with my mossberg thumbhole turkey gun--took it rabbit hunting this fall and the safety is on top of the receiver, far from the grip. With my bulky gloves I couldn't get my hands from the grip to the recevier and back before mr. bunny was gone. No probs when a turkey is coming in nice and slow, but I found it nearly impossible to get the safety off fast enough for rabbits. So I walked the rest of the day with the safety off, NOT something I like doing...the mossberg still kills rabbits though regardless lol
Matt