well, If you try a search, you will prolly get much info about both.
Here is the short, vague answer: Neither, it totally depends on the application, and intended use.
but here is a short primer on the subject.
In an ideal world, a turbo is better, because of its high efficiency, and its lack of need for a mechanical drive doesn't hurt either.
To further complicate matters, there are 2 different typs of superchargers, positive displacement (roots or twin screw style) and centrifugal (vortech or paxton type).
The centrifugal type is very similar to a turbocharger, only it is mechanically driven, rather than driven by a turbine in the exhaust manifold.
Positive displacement is a bit different, in that for each revolution it makes, it delivers a set amount of air. This makes this type of blower great for making lots of torque at low rpm, but tend to run out of breath at higher rpm (ie the Lightning is rev limited to ~5200 rpm because of the blower speed is too high)
Superchargers tend to be easier to package on an engine, hence the aftermarket kit popularity of them. Where as turbos are typically much harder to fit to an existing engine and engine bay, so turbo kits are usually a bit harder to find for a particular vehicle (especially for cars w/ v-type engines, V6 V8, etc.)
Turbos also typically make more power for a given boost level than superchargers because the turbo does not need the power robbing mechanical drive system of the supercharger.
The real downside to turbos is that they don't feel smooth and linear like an S/C, they make little power off idle until the turbo spools up to speed, then the power is suddenly there, big time. A turbo system can be sized properly to keep the "turbo lag" to a minimum, but then if you do that, the system is usually not capable of very large boost numbers. Additionally, turbos are typically harder to tune properly.
I like turbos, but for the contour, the supercharger is the only game in town, until Mr. Hightower's contacts develop a kit, or you want to build your own (personally I would like to build my own, but I understand everyone is not an engineer, nor has the time or proper tools, I know i don't have a proper place to build one up)
Whether one is better than another has far more to do with the application, intended use, and execution of the setup, than any theoretical efficiency advantage.
