If you want a job done right, do it yourself.
There are too many incompetent fools in the world, from dishwashers to doctors. Dealer mechanics and advisers are no exception.
I mod my car so I have even less incentive to let the mongoloid monkey boys touch it.
I took it in for the first oil change. They put 5w30 in, which I thought is a bit light for the car, though I understand it is the recommended fill. Then I chatted a bit with the 12 year old (so it seemed) that changed my oil and realized he was clueless about cars. I wasn't surprised to find my oil was significantly overfilled when I got home. Yeah...no thanks to the Mazda dealer service. If they can't competently perform the most simple of tasks - an oil change, they will not be working on my car, ever.
I do let my speed shop take care of things when I get lazy, especially when I need the tech inspection for a track day anyway. I know him and know well that he is far more competent with a wrench than I. He will be installing my front sway bar because I don't want to be cursing and bleeding in the garage all day on my back. I installed my downpipe, coilovers, CAI, mount, shifter bushings, brakes, etc. Most of it is easy, the hard part is usually getting to a buried part - the downpipe was a little bit of a pita.