I've seen my HD (WD 20gig) is down to $60, and I was thinking of picking up another just for extra performance. But then I also saw some WD 80gig special edition with 8meg cache (reviews seemed positive), and I was wondering if this was better then raid or not?
Depends alot on the app. Small transfers will likely be faster on the 8meg cuz of the huge cache, but larger files/transfers would certainly be faster on RAID. If you already have a RAID controller id certainly go for the striped set!