One of the things I LOVE about my SATA drive is the connecting cable. It's very small and doesn't get in the way, like the IDE connectors I have do. Even though I have round cables for the IDEs, they still have more bulk, are less flexible and positionable, and they still all end in that big 40- or 80-pin connector. The SATA cable ends in a connector that's nice and small, I think it's 4 pins.
I have one of both. I'd like to switch over to SATA completely the next time I get a new drive. I don't really see a difference in performance between them, just ease of connecting, improvements in airflow, and easier access to other components.
The latter comes in handy when you find yourself installing a sound card in a different slot for the 5th time, as I have recently. It could happen to you!! lol
I had a little more trouble setting the SATA drive up, but it came around soon enough. Really wasn't that different; it was mostly because I was used to the ATA standard and how to deal with those drives. They (the SATA models) are probably even easier at this point.
And I have no interest in RAID. That seems risky and unnecessary to me. SATA good, IDE, too. Don't worry with RAID.
Chris