I currently own the MBP described in my sig. It isn't quite the proper fit for my needs. I think a MBA + Thunderbolt display would fit my needs more, and be cheaper than what I paid for the MBP new. Would I notice much of a performance decrease going from this machine to say a 11" MBA with the 1.8ghz cpu upgrade? Only having 4gb ram is bothering me, as I felt Lion was sluggish when my MBP only had 4gb. How would Aperture run on this machine at the Thunderbolt Display's native res? Also, if I sold my MBP how much could I get for it? 14-1500? Thanks guys!