I bought a Western Digital Mybook for backing up my design work after reading a review, admittedly they were using PC, but it said it was compatible with Macs. The Mybook seemed like a good buy as it was pretty cheap storage with a large capacity. When I tried to use it with my Mac it was incredibly temperamental, a lot of the time it wouldn’t mount or it would lose connection when connecting it with either firewire or USB.
I was about to give up with it but after trawling the net found a solution. So if anybody else if having the same trouble instead of connecting the hard drive directly to your mac, use a Firewire hub, it seems to be working for me. Alternatively if you don’t want/need a firewire hub you can chain it via another firewire device. I also reformatted mine to mac format (though it will work without I was having problems with it).
If you are a Mac user looking for a hard drive I would avoid this one, but if you need a work-round for a device you already have give a firewire hub a try.