I've had success using Photoshop 7.0 on the 3.0 crossover release, and things are working very well for me. My machine is currently running Fedora Core 2 (updated from its development tree, though it's pretty much frozen for release) and I've disabled exec-shield and prelink.
I'm going to let some of the professionals here bang on it for a while, and then I'll update the ranking (hopefully to gold!)
cheers,
lars