I've had this one for quite some time, unused. I think in 2008, I brought it to a repair shop to get it working. They soldered something in there (I think) and charged me 50 bucks. I tested it then, but don't think I ever used it since. I must have gotten it because somebody gave up on fixing it themselves.
The following youtube video is me plugging it into a WalMart power station, flicking on the switch, and flicking it off. You can see the light go on and hear the characteristic pop through the speaker coming on and crackle turning off. That's all I got. I'd have to chase down a guitar somewhere to do any better. So, bring your own gear to test it. Don't inquire unless you're ready to buy and just want to ensure it works, though. It's in storage.