Pro-charger is the way to go. Turbo setups need to run leaner at idle/no boost/crusing speeds. They need to run richer at full throttle under a load also. If you throw a manual behind the engine it means the motor will see boost and no boost conditions all the time which means you will need a better stand alone computer also. Even though you will still need one.
Pro-chargers are easier and cheaper in the long run to setup, be efficient, and easier to tune right. Also alot easier to change power wants/needs for your setup. Many variables to consider on this one. Start looking at how much it will be to just build the exhaust side of the turbo situation and you will change your mind on turbos on gas engines