This is for heating and cooling, not the plumbing side of the business:
They are expensive, I will give you that. But they do quality work. I am completely confident that everything they do will be done correctly and on time. They've installed my furnace, my air conditioner, a new chimney liner, and a Mitsubishi Mini Split all without any problems. We had bought a booster fan previously and installed it ourselves and they reinstalled it (better than we did) when they did the furnace.
I only knocked off a star because they quoted me over $900 to do a nitrogen leak test on our copper lineset (which begins at $500). I honestly don't know what goes into doing these tests, but it was about the same amount to REPLACE the copper lineset, so it doesn't even make sense to me to do the test.
So all and all, I rather pay more to a company I trust, that I have history with, than to have a half-finished job for half the price. Just be prepared to feel like you're buying a car with all the price negotiations for bigger jobs.