Hey guys, I'd like to buy a Mac Pro for video purposes. I've configured one on the Apple website but have some questions for ya'll before I pull the trigger. 1) I'm using my education discount to buy from the Apple site, and I like the ability to configure, but if there is a better place to buy from let me know 2) I'm ordering the single quad-core. Is the double really that much faster and worth the extra dough? 3) I have it set-up for 6GB of RAM. Is that a good amount or any reason to do another amount? 4) Is the Video card upgrade to the ATI 4870 worth it and better than the other one? 5) I'd rather not pay for three years of Apple Care, but is it worth it? And any other tips you can give me before I pull the trigger. Thanks!