a single plane with mech secondary carb will outflow (cfm) most of the efi kits, because they are designed for street use. not the electronics part, but the actual size of the inlets/venturi/etc. the physical part is not sized big for very high rpm / high output use.
your mileage will be quite low though haha.
so really, it depends on what you plan on doing with the car. drag race, mileage is your last concern, high output best ET is what matters.
street use, sure you want something peppy but good mileage too and something that cruises smoothly. you want something that can sneak out of the neighborhood without having to run 3000rpm's in case you want to go out at 6:30 am to get coffee and not wake everyone up lol.
so EFI is fine.
i dont buy into the crap that newer is better though. "new technology" does nothing for me. so if i WAS racing on the strip constantly and ET mattered and i wanted a bulletproof setup i probably would not go EFI and probably would not run nitrous. i doubt i would invest in a new hemi since it's not designed to be a racing engine. for the street it's great.