I finally got my Wiz (yesterday actually, but was too busy to really play with it), I had a SD card prepared with all the most interesting stuff I could find, and was waiting eargerly to see how they'd work out.
Overall, I think it's a cute little machine, with some serious and less serious problems..
First up, and least serious (to me anyway), is the OLED display, my machine have one of those OLED's where when showing a single tone on the whole screen, it seems like there is a slight rgb noise filter on, small variations in the color-tone of each pixel.
However, I don't care and find it pleasing to look at anyway.
The size of the things is not really something one should complain about (after all, I knew the size when I bought it), but it's a bit too small for my hands, and after a session of 30 minutes, my hands are compleately cramped up.
The main interface seems slow (to me anyway, knowing that it's a 500 mhz machine with 3D acceleration, I'd expect to be able to scroll down as quick as I can manage to push the buttons), again, not really an issue, but to me it indicates that the code behind the menu must be pretty bad. (how hard is it to redraw the position of a scrollbar.... shouldn't take a noticable amount of time imho)
Now for the one major downside (imo):
Tearing.. I hoped the 1.1.0 firmware would get rid of that, but it didn't.. In the menu, it seems that the tearing is vertical (which makes sense, considering that it's really an 240x320 display), but in all the games, the tearing is diagonal... Like there are two triangles, the first triangle has it's 90deg corner at the top left, and the second on right-down, it seems that the second triangle updates a frame later than the first.. This effect is very visible in many games, including doom, rott, tyrian, jazz, and in emulators like vice.. The only piece of software that seems (to me atleast) to PicoDrive which is able to do smooth fading and scrolling in all the sonic games.. However the (emu-interface)menu fading/switchin still got tearing, which indicates that some hackery must have been employed in order to get the in-game rendering to work properly.
I haven't gotten around to coding to it yet (my first try at SDL seemed to go horribly wrong, it writes pixels in the wrong direction or something like that, something I'll have to figure out when I've got the time.. I hope to write some test-cases for the tearing problem and figure out if there's a software fix for it.. even though I consider things like that to be a OS/driver thing...
[Added on Tue 15 Sep 2009]
I found out that I have a spongy B button, I'm not what you'd call an avid handheld gamer, my last handheld was the Nintendo Game Boy (yes, just "Game Boy") and I don't really remember how the controls was on it, but I've noticed now that if I press the edge of the B button, it don't work.. The other buttons does not have this problem, and it really becomes a problem when trying to play games that require fash and precise pushing (like bombjack on the C64)..
Can anyone suggest a fix for the B button problem, as I'm not seeing myself shipping the unit back to korea to run RMA with playasia..