In a cruel twist that only serves to bump up my post count...
The UK based one I mentioned in the first post has told me that it does indeed use USB for data. I'm still unsure of the native resolution, but it goes as high as 1024 x 768 so I'm assuming 800x600 should be easy for it. With it being in the UK and at £112 delivered next day, we now have a new front runner!