I'm looking to upgrade my WD Caviar Black 500GB 7200RPM drive with a bigger one, in my 2011 MBP 15. The Samsung and WD Caviar Black are the two drives I read about most on this forum and are recommended the most. I'd like 1TB but don't want to spend $200+ on the Seagate 7200RPM. Both the Samsung 1TB 5400RPM or WD Caviar Black 750GB 7200RPM are $110. Would I suffer noticeable performance loss dropping from 7200 to the 5400? Any recommendations for one over the other?