SR3 has not been released yet. Should be in about 10 days per CL. Depends on what you want to do I guess. There are a lot of threads about it here. I suspect you've read most of them if you've held out this long. I never had P4, so I can't compare that way, but my machine is roughly the same size as cruzan's old machine (512 mb ram, 1.7 ghz processor PIV on XP Pro). The speed is not that great compared to Vue and Bryce, but if you have something to do that's not computer related while you're waiting for the renders or have another computer you can use while waiting, it's tolerable :) Unfortunately, I like my XP "eye candy" :) XP pro does help a lot though with the memory management issues.