if you keep your foot out of it and tune it properly (conservative jets for cruising and making up the difference with the power valve) it does ok, not great but ok. if you give into the boost and floor it everywhere like i enjoy doing mileage goes out the window and down to single digits. driveability is decent. cruising and putting around are decent. the only problem that i had was punching it from a cruise. would take a second for the boosters to kick in but all was good after that.
side note. the first carb i tuned for boost i disconnected the secondaries and wired them shut. basically working on the cruising circuit and dialing in the power valve as a 2bbl. just a thought.
i ultimately wound up going down to a 600cfm. pretty happy with it.
