I don't think neither of them will perform much better than the other. The advantage with 4x1GB is that it costs less and by the time you need more than 4GB, I think we'll have moved on to DDR3 as standard.
Now I bought the processor off of Dealiverable.com. I bought it last night and now today I get an email from them saying my order is canceled because the item is out of stock. This really makes me mad because on the item page it says it is available. If it's not available they should say on that page. This really burns me up
I have been looking around to see if I can find any some where else and have not found any that is not overpriced. Looks like if I buy one now, I am going to have to spend $250 or wait until someone gets them back in stock. Even Newegg is a little high compared to some other places.