My MBP has a 500GB right now and I would like to do a 1TB 5400 HDD. I will go to SSD and do the data doubler when the prices come down but for now I need some more room. I do not know what is faster when it comes to these HDDs, like 6gb/3gb, SATA II/III, etc. I'm not interested in a 7200 because of battery performance and not a significantly difference. Any input would be great. Thanks!