I guess I'm the exception.
My local dealer did the initial service, no problems, they
did do the valve adjust, I could hear the difference. Later, I had a problem with a series of small oil leaks, the bike was close to the end of it's warranty, so they told Suzuki I got a bad gasket set, tore down the engine, and replaced all the gaskets in the top of the motor. No problem. Afterward I went over the bike and couldn't find a loose bolt anywhere.
For the major stuff I guess I'll stick with them, a little expensive, but woth the peace of mind.