I have two M500t amps, and had both restored by someone I found on eBay.  I had major/minor problems with both, so I sent them to Greg to look at.  Greg opened them and sent me photos of what he found, and it's clear that someone who does not know electronics can be taken advantage of, as I was to some degree. 

So, bite the bullet and get your amp done right, by Greg, the first time.  You'll save yourself a lot of time and money.  Looking at the attached "before and after" photo, even to my inexperienced eye I can clearly see the difference between the "'eBay build" and Greg's workmanship. 

The amps sound fantastic, and I look forward to many years of enjoyment with them.