I use the western digital passport drives bus powered, I've got a 320gb and 500gb and they have been excellent looking to get a 1tb as I've upgraded my hard drive in my MacBook and the 500gb I used for time machine isn't big enough now
I'm trying crash plan at the minute, my broadband is shite at home so I've had to bring my MacBook to work to upload using infinity but it's only going at 400 kbs like yours I'm only using it for my MacBook to back up my photos so it's only 65gb worth of data.