Q3 Arena does run surprisingly well, except for the cinematics which chug. I turned those off. Shogo MAD (yes, there is a Mac port) has the same problem, but also runs great otherwise. Both games' cinematics play correctly on my MDD in 9.2, so it's clearly system-related. I blame the codec, because the cinematics for, say, System Shock Mac are QT-based, and of course play fine.