Without going further, I have used Mroogle and multiple resources. I decided last week I was going to upgrade my HDD in the late 2008 Macbook Unibody. Initially I got the Seagate 7200.4 320gb, which seemed perfect for me. After 4 hours of use, I couldnt stand the vibration it sent throughout the unibody and alot of people agreed with me. So I returned it for a similar benchmarked performance WD Scorpio Blue 500GB. Right now I can tell you there is a definite wooshing sound (as people described as the calm ocean). Should I exchange the Blue for another HDD (suggestions?) if anyone considers this one defective. Or should I keep my money handy untill the Intel SSD prices go down. I'm kinda leaning more on the performance than space. THANK YOU SO MUCH!! Cheers.