I went ahead and picked up the granddaddy of all laptop hard drives for my MacBook Pro – the Seagate Momentus 500GB 7200RPM with SATA 3.0 (model ST9500420AS). I upgraded from a Hitachi 320GB 7200RPM drive and boy, what a wonderful difference!

Using Carbon Copy Cloner, it took roughly 3 1/2 hours to clone the contents of my 320GB drive to the 500GB. 120GB of photos was the #1 slow down, and #2 was the 320GB drive dragging its proverbial feet. Once the cloning was done, replacing the 320 with the 500 took about 2 minutes – 5 little screws (1 brace and 4 stabilizers on the drive).

The first thing I noticed was that the 500GB Seagate drive boots about 40% faster than the 320GB Hitachi. Apps open up a little faster – not 40% faster, but certainly 20% or so.

Once I’d booted up, I ran several tests and scans on the drive to make sure the drive was going to be stable and error free. Nothing sucks quite so much as banking on a new hard drive, only to have it melt down. Tests showed no drive flaws.

I then ran an XBench test to compare the two drives. The 500GB drive scored well over twice as fast as the 320GB with sequential and random reads/writes. For the non-techies, this simply means that this new Seagate drive whips the snot out of the Hitachi drive.

(XBench is a free utility that every Mac user should have, even if it’s rarely used.)

On the down side, the Seagate drive is just as loud as the 320GB Hitachi. That was a little disappointment to me. That said, the drive isn’t “noisy” per se, it’s just that the spinning is clearly audible in a near silent room or if one listens within 6 or 7 inches of the laptop body. No huge deal.

Other positives? XP boots and runs faster in Parallels. So does Windows 7. So does Linux. Photoshop CS4 opens up 25% faster and runs actions in an instant. File transfers to other 7200RPM drives are way faster. In short, pretty much everything is better and faster.

The best part of all? After Leopard, tons of apps, tens of thousands of photos, etc. I’ve got about 300GB free. Awesome!!

If you’re considering buying the Seagate 500GB drive, I hope these comments help. And hopefully you wind up with a good stable drive that passes any tests you subject it to.