I just played mine a couple of hours every day, I was skeptical of the whole burn in concept but it just kept sounding better and better.

I received my OTS S&M on Friday. I turned it on and let it sit "idling"
Power = ON
Standby = ON
All controls at 12 o'clock

I'd go over and play it every hour or so for a few minutes. I turned it off after about 8 hours, when I went to bed. No problem.

Next morning turned it back on. Same routine, playing it every hour or so.

After being on about 4 hours on Saturday morning, I was playing and it went all distorted/breaking up, started smelling bad and just quit, in a about a 10 second span.

Did some logical procedures and found that one of the 6L6's had a big burn hole in the bottom and was charred between pins 5 and 6 pretty severely. Also the related tube socket was charred rather badly. The fuse in the holder next to the output tubes was also burnt/open.

Talked to Nik and we basically determined that (hopefully) it was just a defective tube? Nik is sending new tubes, tube socket and related resistors that are in that circuit and we'll try again.

The output Xformer was ok. Checked out the windings and all were normal ohm readings.

It was just a bummer because for my next gig tomorrow night I'll still be using my Mesa Lonestar Special (well, that's not really a BAD thing now is it?) 

But, I was so looking forward to the OTS. It was sounding really good...until!!!