I have a Braswell carb on my FE, so I can speak first hand. Before the Braswell, I had a Holley HP Ultra and a QuickFuel. Both very nice carbs and could have been adjusted to do the job well, in retrospect. The problem was that, with my big cam, the car was very hard to tune. I spoke with a ton of people, including some very well-respected carb guys, tech support at Qft and Holley, and a local carb tuner/hot rod guy who is very well respected. None of them fixed the problem, and I was fuel fouling plugs. I then went to Braswell, and Dave Braswell himself helped me. As Brent and Barry say, none of these carbs will be spot on out of the box. But Dave had me iterate a couple of times, call him back each time, and the problem is now solved. Yes, $1300 is a lot for a carb, but this was the only way I could get the car running right. So the main advantage of a Braswell carb is having access to Dave, who BTW is a really nice guy and very willing to help.
But there are other advantages too:
(1) The overall precision, construction, and fit/finish are clearly better than a Holley or QFT. And they do things like include teflon gaskets, which are far far better than non-stick gaskets, etc.
(2) Braswell carbs are not modified Hollies. They are 100% Braswell made, and have some neat features. For example, the floats have a fine line on them. You adjust the float level by removing the bowl and using a caliper. This does make a difference, and you cannot get that close by eyeballing the float glass like you do with the Holley and QFT. They also use a proprietary and patented float bowl design, and flow test each carb.
(3) Braswell carbs look like carb porn. However, they do not come in "colors." They are a very nicely applied old-school yellow
zinc chromate color.
If I had to do it again, I'd buy a Braswell, and I'd do it sooner.