Absolutely, hands down, Qjet. No other carb can provide a more consistent and progressive fuel deliver curve than a Qjet. The single best designed carb ever if you ask me. People think they're no good because they buy an ancient vehicle with 200k on them and wonder why there is a bog at full throttle. If they only knew that all it took was a tiny adjustment with an allen wrench, they might be a lot happier.
Better mileage, vacuum operated secondary metering, a truly CFM-on-demand carb that can't be beat. The bottom line is that if you present that engine with more than about 600 CFMs, it will be too much and you'll lose power. With a 750 or 800 Qjet, it will only open the secondaries enough to let 600 through. Remember, this exact same carb architecture was used on everything GM made for a few decades; everything from Caddy 500s, to 140-hp Olds 307s, and back to 450-hp Buick 455s... and did it all while passing EPA requirements up to 1988.
A close second would be an Edelbrock 1406. 600 cfms, fair to good mileage, easy to tune on the car, and dead nuts reliable.