I admit i have not had much experience with Q3 but i did play it before i ever heard of UT, but once i played UT there was no going back...
UT is just so much fun, and i love the fact that there are a lot of weapons, each with their own style, control, and effectivness depending on the map.
I also agree with blakeatwork, definatly falls somewhere in the middle and i like that 🙂