I am a happy PowerBook user at the moment, but I think about getting myself a sexy G5 PowerMac for desktop use (iMacs are just plain ugly IMHO). Now, the 2.5 Quad would be the cream of course, but it's way out of my financial range at the moment. Question is, how far can the other models (2.0 Dual -> 2.3 Dual -> 2.7 Quad) be upgraded if their CPU power isn't enough for my software? I am much into web programming/design and music, and while SubEthaEdit is obviously quite generous regarding hardware power, Adobe Photoshop, Propellerheads Reason and Ableton Live are quite CPU hungry, especially if linked together (Reason/Logic) and full of VSTi's. Can the CPU be easily switched? Or does it take more than that to upgrade?