I just watched the video on the Onyx website (
http://www.onyx-international.com/en/) and I'm very impressed by their firmware.
I don't like the Ipod-like design of the device, seems quite cheap, but at least their team of programmers actually looks like that they know what they are doing.
their firmware looks far more complete than any competitor, and if it's no unstable/bugged it would be the best by far.