In my experience two engines with the same displacement, one carbed and one fuel-injected, the carbed one gets worse economy simply because it's a less precise method of injection. Fuel is wasted on the way to the combustion chamber.
And throttle response on the street is important and it's 9 times out of 10 going to be better with a fuel injected engine. And with electronic throttle, it's going to be better anyway because throttle tip-in is more progressive and measured and controlled. Just my experience owning a GTO and driving a few muscle cars.
I wouldn't want a carbed car. If I built a muscle car, I'd put an LS motor in it.