Thought I'd chime in here. I bought a used GK NEO 212 II back in June off GC's online used site. Cab came in, gave a quick check with my other neo 212 and mbf 800 and it seemed fine. I think I only hooked it up twice since then, as I play mostly casino gigs and a second cab is just really not needed.
Not really using it much, decided I'd trade it to a local bassist. After running it by itself, sounded like it had some voice coil rub going on,...not good. Pulled the speaker, and then noticed the other 12 didn't match up, someone had done a switcheroo. Not only not good,...now, extremely bad!
I'm almost 3 months out on my purchase, so no return, give my salesguy a call, and after a couple of back and forth's with the manager, they call back and are sending me TWO new gk Neo 212's! To say I was very pleasantly surprised is definitely an understatement.
I know this isn't the norm for GC customer service, or for just about anyone elses service , on used gear past the return date. But I felt it was only right to post an extremely good review since they went way above the bar for taking care of a problem for me.
I've had bad experiences with them too btw, but so far, the good outweighs the bad. I'll keep shopping there. YMMV.