I'm pretty happy with my Holley setup.
I bought a Pro-Form body and some quick change float bowls for convient jet changes. Last road trip I got better milage with the 750 CFM Pro-Form body than I did with my 650 Holley.
Might also be due to a tuning problem other than the carb. Seen that happen a lot. My 68 Merc did it a few weeks ago. Took it out for a few laps around the block ( no license or insurance, so that's all the excercise it gets for now) Started popping at full throttle like it had water in the gas. Turns out the vacuum advance diaphram went south and it was a lack of timing not the carb.
I am having the exact problem, I am trying to get the distributor on a machine so I can take the car above 3000rpms. It is killing me I want to feel the power. I can't even get the tires to hook at 2000rpms can't wait to see what the real powerband is going to feel like.
Did you call Jesse and speak to him? His carbs don't cost a grand unless you want some crazy race piece. He can rework the carb you have for much cheaper than a grand and you don't have to tune anything, you don't even have to set the idle, Like I said, out of the box it will work flawlessly.
In My opinion, fuel injection would only be a real advantage on cold starts since his carbs don't come with a choke, uless you want them that way. I drive mine all year round and the only time I even touch it is to clean it.
I called Bigs. They quoted me $869 bucks. Shipping will be about $20. If they have to charge sales tax, that's about another $80. That's around a grand.
I didn't ask about sending them my carb, but I figure it would be about 3 weeks and $500+. I'm not sure my performance would be that enhanced over a regular 750 DP that's set right.