DBMSTNG said:
turbos are better power adders hands down.
turbo pros - more power, no parasitic drag
turbo cons - expensive, lack of quality kits, heat can become an issue.
supercharger pros - less expensive, easier to install, lots of quality kits. Paxton, Vortech, Kenne Bell.
supercharger cons - makes less power than turbos, parasitic drag.
Define "better"!
Better peak power - yes, does this mean it is a faster car = NO.
As it depends how the power is made and the delivery, also the car and setup play an important role.
Even the Roots blower can be setup to exceed the limits of a stock 2v unit, a twin screw blower will see over 700rwhp on a built 2v motor.
If you are building a circuit racer then a turbo is the way to go, as ultimatly it will produce more power and
should be more reliable. And race cars will always be in the high rpms so even though massive turbo lag exists it does not become an issue.
For road use a supercharger is probably the best setup, for starters its cheaper and it will also work quite well on a stock motor, a turbo needs low compression to porduce the results (7:1 region), which is going to be expensive.
I love turbo cars (have owned a few) but in the case of the Mustang why go to the cost of a turbo setup when a supercharger can be done for less money and produce more "REAL WORLD" power.
If you seriously want more than 450rwhp the the turbo does become an alternative to a supercharger.
FYI - Top fuel dragsters and funny cars use superchargers not turbo's as they work better for drag racing.