I’ve been using metacity as a composite manager for about 2 weeks now and I don’t miss compiz! What I used more in compiz was Alt + tab and transparency, and now I can get that with metacity! And it’s less resource hungry and a bit more responsive. The fancy 2D plugins and the complex compiz animations are in general not useful in a regular working day. Of course they are always nice to show to our friends what linux can do!
So if you want a snapier desktop, but still with some nice effects ans transparency, try metacity again!