i'm using 200s and 250s at home now, slowly but surely. i just picked up another 4 at Fry's a couple weeks ago for <$200 a piece so it's not too bad. still, RAID-5'ing them does make it tricky to get sufficient storage capacity. i'm bringing up ~0.5tb at a time right now with each group (gets expensive).
i'm OK going with standard IDE drives. i understand the risks. i've known a few people who have used standard IDE drives with little to no problems using custom harnesses. the power draw would be the issue for me but i'll be addressing that anyway with the other modifications i'll be making to the car...