RE: Thumb hole stock vs. standard stock
I put a Boyds thumbhole on my 870 slug gun and absolutely love it (and I personally think it looks great). I don't find follow up shots any problem at all, and the crossbolt safety doesn't require any change in hand position.
I also have a synthetic thumbhole stock on my Knight Disc Extreme ML. I think it really helps, especially with the extra barrel weight hanging out there.