Chainsaw Repair

OK, not exactly a chainsaw, but close enough that I'm hoping someone will have some feedback for me:

I have a Jonsered GR3026 brush cutter that seems to have lost compression. I made the mistake of letting someone use it while we were doing trail maintenance on some group-owned forest land. He SAYS he only used the gas can I pointed out to him (my own, which I filled and mixed myself). That may or may not be true: he did refill it twice. Toward the end of his operation, as he got nearer to where I was working, I did hear that he was operating it at WOT all the time, even under no load when not in the brush. When he had finished clearing a large area of brush, he brought it back and mentioned that it was "smoking" toward the end and died on him. Could just the WOT with no load for some extended time have caused this, or is it more likely that this was in fact straight gassed? Is there any easy way to tell the difference from the wear/damage pattern?

A few days later I pulled it over and it just felt strange. Not much compression. Would not start.

I brought it to a local chainsaw guy and asked him to check it over. His report was that it appears it was straight gassed. His comment was that it was not worth fixing. I've since heard that he is not the greatest repair guy around (unfortunately, most of the really good old timers in my area have retired and/or passed away.)

I have never attempted to replace a piston and cylinder myself. How tough is that on one of these brush cutters? are there other things that probably got toasted as well, or is it most likely just the piston and cylinder?  Are parts still available for a GR2036?

There is one other guy in the area who does chainsaw repair. He has a better reputation for repair, but had a huge backlog of work ahead of me when I checked with him a while ago. I may run it past him.

I'm not sure if I have the time to tackle this myself at the moment. Does anyone have a feel for whether this is worth fixing, or should I just send it to the parts bin?

I dont know anything about a jonsered GR 2036

But the stihl and husky ones sure are worth repairing. So I would think the jred would be too.  Bet a husky or redmax version of those anyways.