About this same dealer, he installed a 750 in an old house with a new B & G circulator. The owner complained that he could hear noise from the new boiler when sitting in his living room and when trying to sleep. The dealer was back several times and couldn't find anything wrong. The owner called efm and I went out on a warranty call, actually two times. The dealer was through with him and called him crazy.
The guy was definitely eccentric, but I did hear the noise. The dealer is hard of hearing and didn't. I said it was the circulator. The dealer said it was quiet to him and he has a thing about the Taco 007 that he won't install any. I said I'd take the B & G back under warranty, even though there was nothing wrong with it. They can be noisy. He installed the Taco and it was quiet and I never heard, nor did the dealer, from him again. He was happy.
I saw the dealer recently and asked him if he had a change of heart for the Tacos, and he isn't ready to switch yet.