I think most of the people that have trouble with Raid on ABit MoBos are attempting to use a SCSI card and don't disable the on-board Highpoint Raid controller in BIOS. Or even worse, they try to put drives on both.
If you are using a SCSI card, an ABit with onboard raid probably isn't the best choice in MoBo. Otherwise, it's great
I think you might have some difficulty with different brands of HDs making up the array though. I have always understood that it is best to have HDs of the same size and brand.
Mode 0 (Striping) lets you move around large files faster (hence, faster start-up of OS and Apps.)
Mode 1 (mirroring) lets you have a real-time back-up of all your data in case an HD fails (mechanically/electrically). (won't help if failure is due to bad software and/or set-up because the mistakes will be mirrored on each drive)
It doesn't really sound like you are doing work that would show major changes in performance with a Raid Array, but it is kind of fun to hobby around with..........
GO FER IT!
note: I use the additional IDE connectors (as non-raid) to allow each drive to be the master (when possible) and keep ATAPI devices off a connector servicing an HD (at all costs)