With my 9500 pro, image planes won't show up at all for some reason, and using sculpt nurbs surface is very buggy. After I installed FireGL drivers it was fixed.
Unfortunatly ATI's drivers are still buggy in other things. I can't hit esc in half-life unless I'm using older drivers, and the Linux drivers don't work with glibc 3.2 and xfree 4.3
If I had it to do over again, I'd buy a gf 4 ti 4200, OC it and mod it into a quadro.