i watched the movie and i think its excellent!
any one who has been connected to the internet for the last two years should know its not historical. Its something like an epic sin city. Great effects, great battles, amazing style and so so acting,lol(of course sin city's acting is top notch, at least the actors are good)
now regarding the landscapes...the thing is that in my opinion general 3d apps like maya or 3d max are always best. they are more flexible. Terragen should be fine for mid to long distance landscapes, but the others are better for close-ups...at least for now.