You're going to get a lot of anecdotal evidence for both sides of the story here. The short answer is, if you get good quality hardware to go with it, Intel vs AMD mostly doesn't matter. We've seen people post here with good success on both CPU vendor's products. The key is to stick with what you know or do enough research to find out what's the best setup for that particular processor. It sounds counterintuitive that you'd need to do this but there are certain combinations of hardware that are known to work pretty flawlessly unless you do something really screwball. Look around here at the basic setups folks use that have been doing it a while and you'll have a good baseline model to start with.

Good luck!