that's true, I actually get worse mileage in my RS (25-28mpg) than I did with the WRX (26-30mpg). Just proves that proper engine tuning for all motors is important.
I get the same amount of miles, 300, from a tank of gas in the RS or the STi, with me daily driving them. If Al drives the STi, mileage is GREATLY reduced.
On the highway the RS sucks up the gas due to the gearing.
the only thing i have had luck with with N/A is go light weight! and let it breath! light weight crank pulley, light weight flywheel, intake, and larger exhaust work great. but like others said bang for your buck is just making it go around corners faster!!!