Why would you compare a 650 Edelbrock to a 750 4150 style carb, that isn't the question? Furthermore, wouldn't a direct comparison between the 650 Edelbrock and 750 Edelbrock be more inline if trying to decide on cfm requirement for a given engine? For those that like the 4150 style carbs, a comparison between the 650 dp and 750dp would likely tell a story also.
On the dyno, my W2 408 made significantly more power with a Quickfuel Q950, vs same model carb in 850cfm version. That to me is a relative comparison.
I sure see a lot of guys running stock, and superstock that can go really fast, making big power with the AFB, AVS style carbs.