

I've got a P35C DS3R and I've had no problems with it at the mo. But semi-pro waster's much more experienced than myself so you might want to take his advice on getting the DS3P. You could actually get another 8800GT eventually as well if you got a DS3P (although I'm not sure if it actually supports SLI).
The DS3P does have Firewire, Crossfire and a couple of other things that the P35C DS3R doesn't have but if they aren't important to you then it isn't a compelling reason to spend more cash.