I finally saw it yesterday and I guess I give it a C. If it wasn't a movie about flintlocks, mountain men and guns/horns, I wouldn't even be remotely interested in seeing it again, it just left me feeling rather, "mehhhh" about it. My wife liked it though and I was concerned that she wouldn't. The language didn't bother me, nor did the length of the film, I guess it was mostly the historical accuracy and mistakes with the guns that put me off, though there was something else too and I can't put my finger on it.
I thought the acting was very good and the scenery was nice. Seeing flintlocks and mountain man themes (beaver trapping for instance) was nice. When it comes out on HBO and shows up in my living room, I'll probably watch it again, but I won't buy the DVD or make it part of my regular rotation.