When I was racing I was lucky to have a local carb guy here in the PNW that was well known to build great Holley carbs. Again, it was back in the day before all of "race ready" carbs were available at the click of a mouse. Hell, a mouse was a SBC!
You'd go buy a 3310 from Super Shops, drop it off at my carb guy, and have a full on race ready carb in 2 weeks. Choke horn milled off, bowls blended, downleg boosters, 4150 rear metering block installed, rear jet extensions and new floats, 4 corner idle circuit, monkey with the air bleeds, etc., etc.
He finally retired from building and servicing race carbs about 8 years ago. But there are some of his loyal customers (like me) that he will still build carbs for out of his home shop. I just had him build me another carb for my truck this past spring. So I feel very fortunate to have him still available to me. He has taught me a lot about Holley carbs and also engine building over the years.
Some of my buddies that are still in the racing game and also some of my hot rod buddies think I'm crazy to still have a stock Holley built buy a carb guy instead of bolting on a Quick Fuel of a Holley HP. But... this cat builds a mean carb and his services cost me about the exact same (including the cost of the carb) as a direct bolt on. But when I was racing and needed a bit of help in the pits, he was available for free to come see what I needed. He was always at the track and always helping customers dial in their rigs. That local service isn't available from QF of Holley. Also, if there was a problem, I could take the carb back and the turn around time was toot-sweet. No boxing it up and sending it halfway across the country. So, call me nostalgic or whatever... but I'll continue to use a local guy until the services are no longer available to me.
Gary