I upgraded to the 15K Cheetah from IDE Raid about 5 months ago. All I can say is there is no going back (well at least on my main computer). I keep an IDE in the computer for storage, mp3s, and Swap file. So I get the benefit of speed and space. When the Cheetahs come down in price I am going to hook another one up to my Raid Card, woohoo. If you are on a budget, IDE is still nothing to bark at.