tuned correctly you can see the same mpg's turbo'd as a n/a car .... either way ... yes it cost to turbo a vehicle but do it right it will be as reliable on gas and dependability . and the one thing with a turbo it will help gas mileage .. supposedly a turbo Atomizes (sp ) the gas and more gas gets burnt instead of shooting out your tailpipe under acceleration .. but either way can be argued ..... do what YOU feel is best .. not wut everyone else thinks .