Raptor (150GB) versus Seagate Barracuda 7200.2 SATA

I've been looking at the 150GB Raptors, for their speed at booting up and their speed handling other tasks. I currently have a three year old Seagate Barracuda 7200.7 SATA drive with 8mb cache.

Does anyone have experience with both of these drives? I'd like to know how much louder the raptor would be compared to my current drive.

After the raptor, what is the next best (speed and performance wise) comparable drive that is quieter? And how would it compare to my current drive?

SilentPCReview.com has a good number of articles pertaining to that kind of performance v. noise stuff. I don’t quite remember but the Barracudas are very well like on that site. I myself have an older IDE WD drive that runs on ball bearings - the constant whine is the loudest part of my computer.