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Depends on your rpm range.....
PERFORMER® MANIFOLDS (Idle to 5500 rpm)
PERFORMER RPM™ MANIFOLDS (1500 to 6500 rpm)
The rpm runners will be higher volume and are intended for use in a higher rpm motor where runner velocity will be high enough to pack the cylinders properly. On a daily driver, the RPM will not be passing enough CFM to keep velocity up for good cylinder packing and the motor might run worse than it did with the stock manifold, particularly at lower rpm's.

if you are not changing anything else, the performer is your better choice, not the rpm performer. Dual plane is a better choice for you.

Either manifold will work as they are both dual plane though Edelbrock claims a higher RPM band for the RPM version.

A 750cfm carb is WAY, WAY too big for a street driven car that sees little high rpm operation. The OEM 460 Ford ran a 500-525 cfm and got reasonable(??) gas mileage for the time. I tried a 780 Holley 3310-1 on my long gone '79 460 truck - gas mileage went from poor to abysmal and with the performance also going away.

Here's the industry accepted formula for determining carb cfm:

CID x RPM x V.E. / 3456 = CFM

428 x 3000 x .85 / 3456 = 315cfm

428 x 4000x.85 / 3456 = 421cfm

428 x 5000 x .85 / 3456 = 526cfm

428 x 6000 x .85 / 3456 = 631 cfm

Looks like I'd be considering a 600 to 650 max carb Which means at any of these RPM figures, you don't need that much carb. And with gas at $3.75/gallon,,,,\\\\\////???