I'm going to have to +1 everyone else here.
I don't know manchovie but he seems like a good guy and if there's a lot of vets willing to back him up then maybe you should step back from the situation and look at it from an objective approach.
Just take it easy and ask in a calm manner what he can do for you to remedy the situation and make things cool. That's the approach I take and I'd like to think that I'm a good customer but also one that demands good service and gets it because I'm so "easy going". I know it's not easy sending your expensive stuff out to repair centres and whatnot but if you take the time to look for a good one and are an easy client to deal with then it should be no problem.
Currently I have one of my guns (worth about $400) at a gundocs who lives 3 provinces over. I approached them around October and they've had the gun in their possession for a couple weeks now. I'm not worried because he seems to be trusted and it looks like he does good work. I'll check up on him once in a while obviously but I'm not going to pester him every day.
As for the Troy M7, well AR15/M4 pattern guns should usually be pretty easy to work on and I've done work on some M4's before but the MP5 I wouldn't know since I've never worked on one (not on the externals anyways). As for the M4 being hard to disassemble, that could be the case if you're wired for a connector that doesn't go through that notch on the bottom of the barrel cleanly as is the case with mine with deans which is a bit hard to do.
ಠ_ಠLess QQ more Pew Pew
READY TO >> RACE