Picked one of these up from eBay last month, only took a little over 2 weeks to arrive. I was always put off by the smaller screen size of the RS-97, so that's why I was attracted to the RZX-50. Mine has an analog nub.
Screen has a couple little scratches. Not sure if the top layer of the screen has a peelable protector or not. One dead pixel, near the center =\
Came installed with version 1.5006, and with english language selected. Installing the latest firmware now, thank you to Jutley.
Edit: so I don't have "Settings => Software Update => OK". I have System->Auto Upgrade. When I do that, it says "Checking the Update File... Press A to quit." and stays like that forever. Any ideas?
Edit 2: all of my pre-installed (no update done) built-in DGE emulators have date 4/11/2012 8:38 PM except for gba_emu.dge which is 5/15/2012 12:42 PM. I have psx.dge as well as bios file scph1001.
Edit 3: wow, after playing with the emulators, this thing has serious issues
CPS1 - can't edit key config. it gives me the options, but nothing takes effect. When playing fullscreen, it's stretched and seems like not 60fps. what is 'gsensor'?
gb/gbc - games run at 2x speed
sms/gg - games run at 2x speed
gba - seems to be ok
nes - controls are STUCK at holding down. sprites don't show up
sfc - can't press up
smd - only .smd files appear. STUCK at holding down.
unplayable junk so far. hoping for a miracle!