I've got the PC version on my puny little Win98 notebook with no serious problems (haven't installed the patch yet). But I'll be at the front of the line to get the Mac version when it's out - can't wait to use all its goodies on a real computer! So far, P5 is worth it JUST to be able to group all my morph dials, to nest library folders, and to have a professional material editor. I think I'll find displacement mapping very useful, but I haven't worked with it yet.