Don't have it, but it certainly is very interesting and has lots of potential.
Sure, I wish that some things were better; bit more polish as in; slightly prettier looks, no sound distortion if you turn up the volume... things like that. And that the SNES emulator had better compatibility.
Anyway, from what I've heard from people who had the predecessor, GP32, it seems that they really liked it. Of course, these are not your average PSP/DS-owners, but a very select folk, so they'd be more likely to put up with some minor issues the console might have had.
So, all in all, if I had extra money to spend, I'd certainly consider it. It even has fMSX, so...
And like Darkness said, wireless connectivity would be very nice. Combined with a platform that supports Open Source, all kinds of cool things might happen.