It seems ok but I've never heard of them and the price is a little cheap for what they seem to be offering. Not sure how well I'd trust them, personally.
Note also that your data isn't stored encrypted on their servers. Also, no mention of any data integrity checks or anything more technical (though I didn't look too deeply into the service).
I personally use
strongspace, which also gives you productivity tools (email etc.) and web hosting for one price. And I can vouch for the service; the guys that run it know their stuff, and the systems they're using are very advanced as of right now (they use the ZFS filesystem, which does snapshots and automatic data integrity checks and all sorts), and in fact I think they were the first commercial application to use ZFS. It's also web-based so you can get your stuff from anywith with an internet connection, as well as access from any application with SFTP capability.
However, if you just want cheap, reliable backup, then take a look at Amazon's S3 and jungledisk:
http://www.jungledisk.com/
You'd be very hard-pushed to beat Amazon for their storage capabilities and prices, and jungledisk is just an interface for that system on your computer.