I just want to concur with Essentialaudio that at 500 hours the JC1-1's are quite boring. I had been "piece mealing" the break-in time and keeping track of the hours. I knew about the long break-in time, but was becoming impatient. So I wrote to Crump and told him of my concerns and he talked me into leaving these bad boys powered-up 24/7 with signal. I didn't want to do it, but I promised myself that I wouldn't prematurely cut my loses and sell these amps until they were fully broken-in. Also. I wasn't looking forward to the power bill, but at least it wasn't summer (Arizona) and it wasn't that bad after all. My amps now have well over 2000 hours and they continue to blow my mind. And they took another quantum leap forward after I put aftermarket pc's on them. This may seem like an extreme and an exorbitant amount of time to break in a pair of amps, and perhaps it is. But the returns are well worth it. But I could totally understand someone taking a pass on JC1's for this reason. Also, I'm convinced that many people prematurely sell these amps, unsatisfied with their sound, prior to being fully broken-in. I posted to this thread because I also had 7b-sst mono's on my shortlist of amps at the time. I couldn't audition either amp, so I did a lot of research and homework. Which included talking to owners of both amps and speaking to people in the industry. Also one of the things that really bugged me about the sst's were that they didn't have dual binding posts, something I just can't understand in today's market. So, in the end, I ordered a brand new pair of JC1's and have never looked back (well, at least after the break-in:).