A supercharger takes power to make power because it opperates off a pullie on the motor draining some of the power that the motor itself should be putting out where as a turbo just recycles your unused exhaust fumes.

An egt is also very necessary to have tapped into your manifold to tell you how hot/cold your manifold is running so you can have an accurate way to tell if you are running lean or rich. You have to remember a turbo pulls out alot more of your gas and where as when you aren't in boost you may be running perfect but the second you hit boost your injectors are putting alot of overtime in. You don't wanna lean it out to bad and blow your shit up.