its true that the hanvon has windows ce too, but the firmware from the e/c920 is not the same as on the jetbook color! it is very different from the jetbook, it seems they are being coded individually from each company
in asian reviews the software actually gains positive feedback!
The JBC is a completely different design hardware and software-wise. Don't forget the E/C920 has a capacitive touch to (actually working without another additional touch layer) see
Hanvon dual-touch
Maybe I am a bit enthusiastic about the Hanvon, but this is also because im considering getting it. I have to say I don't like that it looks the same as the JBC and has a windows ce (based) firmware too, but from the users who have actually bought it, they seem very happy with it also with the firmware