I believe a properly sized turbo would be more efficient than a turbo and stupercharger. now if you wanna go fast and fairly cheap, get a 94ish mustang GT with a MAF, buy like an incon turbo kit and run the car on the ragged edge of block splitting power (500hp). But turbos are verry fun
. But remember if your gonna make big power out of your car, you have to look at your transmission will it take it? will your axles hold it, will car car twist like a qork screw. And most importanly if you want to go fast you gotta stop faster, dont forget your brakes etc.
*thinks of the lack of good brakes on my turbo stang*