Their service is good along with their website.
Why are they good?
We dynoed with my stock original 780 BV Vac secondary then went to a Barry Grant model tick looking with all the bells and whistles and after went to the little sleeper looking AED. That was the one that made the best power. It flowed like a 900 but snapped like the 750 should.
Sorry, I can't be more technical than that. When it comes to carbs, either they are right or not.
I have 2 identical Nascar Carbs fro my cup car and one is much better. I can't figure out why but I know which one stays in the trailer.