Guys, I just ordered a refurbished 15" 2.53ghz, 4GB RAM, 320GB HD, Geforce 9600GT with 512MB, for $1449 just because I couldn't pass the deal. The thing is: Besides the SD card slot, better battery, 500GB HD, and the 2.8Ghz/3.06ghz processors options, is there anything else that would be worth paying $850 or even $650 (with the Education Discount) MORE to have the Summer 2009 high-end model? Is there any visible difference on the screen? Anything would help, maybe I missed some detail. Thanks!