IMHO, the privately funded Indian complex is far more interesting than the government funded facilities supporting the close by Mount Rushmore, where Washington, Jefferson, Lincoln and T. Roosevelt stare out over the land. Both sites are beautiful, but the government sponsored shops and displays are rather bland by comparison.
I agree. Even in it's partially completed state, I found it truly impressive. It is a fascinating project, that a number of people have dedicated their lives to. It's well worth visiting.