Carter=economy/reliability Holley=Better straight line performance. You never blow out a power valve on a carter. I have one on my 360 and it really sucks. But of course it is pretty beat so I can't really compare that to a new one. There is better fuel mixture on a carter because of the venturi design.
74 Charger SE
87 Shelby Lancer
80 1 ton bread box
71 Duster rest in pieces