Summit Racing sells the Edelbrock 1406 for $285, The Holley 4106 for $275 and a re-manufactured QuadraJet (750cfm) for $269.

Price really is not an issue - All work well and all have their advantages (and quirks).

The QJ sounds really great when the secondaries open and Chevy has used the 750 QJ on everything from a 305 to a 454.

The Holley has been the racer's choice for a long time.

The Edelbrock is really simple to tune with a very complete range of valves and jets.

It comes down to what you want to run.

Kind of like, "which stereo is the best? Sony? Kenwood? JVC?, Bose?"