Well there are a lot of folks using PF500's with no problems, but it does suck when you get one that doesn't work, I'll certainly admit that. But Ampeg's been very quick to hop on problems and get new amps to those with problems, so I'd give it another shot. Of course, I'm a little biased

but trust me...nobody at Ampeg wants you to spend your hard-earned on an amp that doesn't work.