I've noticed a difference in a couple areas. The biggest one being the time it took for my raptor to format. Second being the time it takes windows to load, and third being the time it takes for maps to load. But does that justify paying almost $200 for 74 gigs?
Hardly.
Do I regret it? Kinda. It's performed great and did exactly what I expected. I mean it's a hard drive, you can't expect hard drives to do much considering how limited you are.
But would I buy one again? Probably not.
Recently it's been makeing some noises like its DIEING. But WD has a 5 year warrenty on it, so I may have to send it in.
I'd suggest buying two WD 80 gigs and setting them up in a RAID-0. They're already great hard drives, and only $40-$50 depending on where you look. And I'd bet two 80's in a RAID-0 array would be on par with raptor.