My Tekkeon MP1550 arrived in the mail today. First impressions are that is very small (~30% larger than 4xAAs), looks nice but is pretty flimsy - sliding battery door isn't super secure and may come off if the unit loose in a bag and the on off switch seems a little loose. Shiny black finish is a finger print magnet

Still seems to do the job - quick check shows it charges the N800 and can at least spin up a 2.5 in hard drive - however it was reporting 'missing filesystem' which I guess might be down to NTFS not being supported?

I'm charging up the batteries (4xAA eneloop) now - hopefully get a chance to run some benchmarks in a day or two. I still dont have a great test - perhaps I'll try running mplayer repeatedly from a shell script in an xterm.