I'm starting a course in graphics and art at my highschool and it requires CS4 (usually more than one app at a time). My current macbook pro (13" 2.26) is struggling so i'm thinking of getting and iMac (21.5 with 1TB HD). I dont really care about usb 3.0, and the most intensive thing i will be doing is probably CS4. However i will need it to last 3 and a half years. Will it be redundant in 3 years or should i wait for a cheaper quad core iMac?