I do like the Thors for hunting, especially the feature of being able to get the correct diameter bullet that fits your particular barrel. Old Hunter is a real proponent of them, he turned me on to them and thats what I use. But all bets are off now as I'll be getting a new M/L in a couple of months....as soon as I get to the Grand Junction Cabelas. The I'll start with a clean slate.
As far as powder goes, I use nothing but substitute American Pioneer Powder (APP) or Goex (real BP). I shoot competation Cowboy Action and use only BP or APP. IMHO APP burns almost like BP and is easier to clean.
Check back in this catagory history and there are several reall good threads on M/L and bullets.