The thunder AVS are great. the 800 works nice with a 440. Much better effort than the "street avenger" series by holley.
Their operation is very easy to tune. If you have the right sized carb, it works.
With a 3.73 gear, perf exh manifolds, and summit 1103 cam, action + manifold, the 650 AVS ran the quarter in the low 14's. In a GM 350" V8 swapped buick skyhawk.
The 750 Eddy is nothing but trouble. It's a poorly designed carb. There have been hundreds of posts here with people having trouble with them. The 800 Thunder is a whole different carb.
I know someone who has a well used 750 carter afb on a low budget 408 small block mopar and it doesn't miss a beat. I have no idea if the carter is better or different than the edelbrock carb though.
My brother has an 800 eps on a 455 buick and it runs out nice. I wouldn't put one on a stone stock 360, but I think it would work if the engine was modified somewhat.