hey. Just think about upgrading the hard drive in iMac, how neccessary it is . The cost you pay per GB is much higher in iMac for the internal H.D. . you can get external H.D (usb/firewire) with much more GB\TB per dollar, and also to utilizing the time machine option, as well as the advantages of external storage drive,it's portable, much cheaper per GB and also more comfortable to work in case of fault. any thoughts ? p.s.:sorry for my poor english.