I mostly surf the web, etc., but 1) I want the laptop to last 5 years, 2) I want to run at least 1 external monitor, and 3) Sometimes I'd like to run Flight Simulator X (graphics intensive). So I've decided to upgrade to 16GB ram. But what do I do about the processor? Leave it at the basic i5 ... jump a bit to the mid-tier i5 ... or go to the i7? Thanks.