It's a bit more about the people behind the counter than the bike shop itself. I wouldn't try to pick the "best", but if there's a shop near my house that understands what I'm saying and is able to help, they get my business.
The parts they can get depends on the distributors they deal with. If you have something specific in mind, show a few shops your shopping list.
Haven't run into a dishonest mechanic, but there have been times where I've had misunderstandings. Even then, I've been offered solutions to improve the situation.
Good luck with your bike project.