External HDD Cage w/ Software RAID1

I've been looking around and found, or I think so, a low-cost option for what I want to do. I'm looking to do a software RAID1 setup for my MacBook Pro. This will be used for backup of pictures/movies/family videos/music/etc.

I'm currently looking at this setup:

Amazon.com: Cooler Master 4 in 3 HDD Module Device - (STB-3T4-E3-GP): Electronics
Amazon.com: SATA/PATA/IDE Drive to USB 2.0 Adapter Converter Cable for 2.5 / 3.5 Inch Hard Drive / Optical Drive with External AC Power Adapter: Electronics

I know this cage is for use within larger tower cases, but I find it to be a nice, separate enclosure for multi-HDDs.

I'm choosing this cage setup vs. a multi-bay enclosure so that each drive is independent of each other in terms of USB and Power vs. only 1 USB/Power on the enclosure. This way, if something goes wrong in the enclosure, both drives are affected vs. with the cage each HDD is easily manageable apart from each other.

I'm looking for any thoughts or suggestions anyone has. Let me know if this is a good route to take, or if there is something better you suggest or I'm overlooking.

Thanks.

Skip software. Since you're buying equipment go hardware RAID. All in all it's 100% superior.