So I am using the student discount to purchase a new macbook pro. I'm not sure which is more worth it. The lower end MBP is $1899 with the student discount, but the higher is $2299 which saves me $200 instead of $100. Can someone explain to me the stuff like 5400 rpm vs 7200 rpm? and how it affects battery life. Also, the ram and GHz; is .13 worth the price and is it an improvement that I will easily recognize? Last, is 256 MB of graphics memory significant?