It totally depends on what you are going for. Some superchargers are known for excellent reliability (Eaton/Magnuson roots types have been known to last over 100,000 miles) but are limited in power potential. Turbochargers are will known for having vast potential and requiring a bit more TLC and maintenance than most superchargers. The fastest cars bearing J-body names are turbocharged, and the fastest cars on the J-body.org are turbocharged. But it's likely that the most reliable boosted cars are those running low levels of boost with the GM Supercharger kits. What are your goals and priorities? Turbochargers offer the option to easily upgrade to more boost, while superchargers can generally have a set boost limit. Adding smaller pullies to superchargers can get a couple PSI, but for our vehicles, a supercharger will never out boost a turbocharger.
