Since i first saw this film back in the 80's I've been trying to track down my own copy of this film.
100% respect to Fritz Langs original, which i own anyway, but the music and work that was put into this version makes it, in my opinion, the definitive version (sorry purists!).
If you've not seen the original buy that version first, then this version to see just how amazing it really is. Ok, the film is 2 hours long and watching both versions will cost you 4 hours of your life - but they wont be wasted.
Historically this is still one of the biggest films ever made by way of cast, sets, special effects (WAY ahead of their time), musical score (both versions) and cost to produce. Every film enthusiast and indeed anyone who just loves a damn good story should own this film and the added benefit of the Georgio Moroder soundtrack will only make it better.
You absolutely will not regret this purchase.