Not real keen on the China-made Edelbrock carbs. They're manufactured to meet a price point rather than a quality engineering level.
The Edelbrock 1406 is a 600CFM unit. The Rochester M4ME Quads are 750 CFM units with 1-3/32" primaries... Rochester made 800CFM units with 1-7/32" primaries for Cadillac.
The Edelbrock is a very raw design that uses mechanical secondaries that open regardless of demand so it can easily run overly rich when you step on it. An overly rich mix can wash the lube off the cylinder walls causing accelerated wear. The Rochester is a bit more refined in that it has vacuum secondaries that only open when the engine needs more fuel and will actually burn it.
The Rochester M4ME & M4MC also compensate for altitude with a mixture compensation aneroid and a fairly refined metering assembly. The Eddy has to be tuned for your operational conditions and, just like the universal Holley carbs, they aren't very forgiving of altitude changes.
IMHO A properly re-built Rochester Quadrajet M4ME will run trouble-free for a lot longer than China-made Edelbrock and the Rochester will perform very very well. The Rochester also uses less fuel when you're just cruising and still has decent power on-tap without wasting fuel when you step on it.
http://www.generationhighoutput.com/Quadrajet_Service_1981.pdf