Tier 1 (these are great movies, his best): Blow Out, Carlito's Way
Tier 2 (these are all very good. I don't think they're all equally good, I just don't want to try and rank them without rewatching them): Sisters, The Phantom of Paradise, Obsession, Carrie, Dressed to Kill, Body Double
I'm not assigning "tiers" to these last four, since the rankings are very definite
The Untouchables - Good commercial entertainment. The shootouts a kind of great but, unlike his Hitchcock movies, they're more enjoyable if you don't spot the homages (which I'm 100% sure he wants us to spot).
Scarface - Overlong with some long boring parts, but also some redeeming good parts. Does not deserve its reputation, but there's enough there to push it into the "worth watching" category, IMHO.
Mission: Impossible - Workmanlike and boring, despite some good visuals.
Casualties of War - Garish, campy, stupid "message movie," as if he was trying to make the worst movie he possible could. It's alot less boring than Mission: Impossible though.