Yeah, IF you do those things. Not everybody wants to muck about with them all that much. Shaping the bolt can leave you with a useless shotgun if done poorly. I've done the shoulder stock/PG conversion on mine, and it was easy enough, but at some point you have to ask yourself just how much time and parts you want to throw at the thing, because at the end of it, you have something that throws lead shot just like any other shotgun.
I just can't give a flat recommendation to the S12 for any and every purpose like rottieman tends to do; unless an owner is willing to put in a fair amount of time and money, it just isn't head and shoulders above competing shotguns of a more traditional design. If you are willing, well, yay, but you aren't going to be doing things that much better than the guy with the 1100 Tactical, FN SLP, or 930 SPX.