I'm not concerned about Windows start up time or program launch times, what I would like to know is, what would be faster when running a defrag program, or my spyware applications, ie: SB S & D, A squared, virus scanner, ect? A Raptor or a newer, larger hard drive? Thanks.

You can compare the two here http://www23.tomshardware.com/storage.html. I think overall at least a couple new drives beat a Raptor in some cases but they are also have more space and cost less per GB. Overall I think that unless you must have the best possible speed then you should get a drive like a Caviar SE16 which is huge.
Hope I helped

Thanks.

I have a Raptor and the WD 500G caviar. They are both fast. I still find the Raptor a bit faster in most things. Seek times on the Raptor are sweeet.
Like DJ898 said, the price per gig and performance of the WD caviar is almost unbeatable. But if you have the extra $$, you wont feel you wasted money getting a Raptor.

15,000 RPM SCSI. http://www.newegg.com/Product/Prod [...] %2c000+RPM

Spindle speed = faster seek times. As far as windows startup performance nothing touches SSD's.