I have an early 2009 MacBook with the default specs. Do you think will this update be worthing? 1. Buying 4Gb of 800MHz RAM 2. Buying a 320Gb 7200rpm HDD and replacing the 120Gb 5400rpm HDD 3. Buying a firewire case to have the 120Gb disk available for... say... virtual machines... do you think it will work? Will 7200rpm disk work with no problems? I read somewhere such disks get hot easier than the 5400rpm ones. To firewire or to USB? that's the problem... is the performance difference heavily noticed between using an external drive connected to firewire or to USB? 800MHz memory will be fully used? the specs say 667 is the top but a lot of people said that the 800MHz is supported anyway.