I've had a bad run as of late with used amps from GC (albeit guitar amps). One made a loud SNAP (which sounded like a component reaching end-of-life) when I shut it off, followed by the scent of magic smoke leaking out. When I returned the amp and described the problem, the sales guy plugged it in, played through it finding that it still worked. He dismissed my experience (which I know what I heard and smelled as I hear it and smell it during my day-job at UL). Another amp came with a burned out power tube, or worse (I didn't look inside). Back it went too. I was rewarded by having my account flagged which effectively blocks my return privileges. If they're willing to remove it if I find something I want, I'll try again. If they maintain their "no returns until you keep some stuff" line that I was given, I won't be doing business with GC again.