They're a fully-accredited panel beater / body shop and most of their work is from the insurance companies, so they are technically able to do any kind of body repair work. Having said that, I'd personally draw the line if it requires aluminum welding. If it's that serious, you're in insurance claim territory anyway and should require an accredited Tesla body shop to do the work (it's the same excess to you regardless). Quest are definitely worth a look for anything where you wouldn't be making a claim (eg resprays, minor dents etc).
I'd also add that I found Ash from Quest a decent, down-to-earth guy. By way of contrast I had a very unpleasant, pushy, arrogant vibe from the Tesla accredited body shop manager.