I would go with MagnaCharger. Direct bolt-on replacement to your intake manifold, its not centrifugal, and the polished model looks $hit-hot! Truckin' magazine did an article on an install on a 5.3L, (Volume 34 No.8), from August I think. Im looking at it right now and its very informative. They are claiming over 400 ponies at the rear wheels. It uses 1/4 HP at 60 MPH, so whoever said that a blower kills your mpg, is thinkin old school. According to this article, it actually improves mpg as long as you arent throttling like hell, but lets be honest, if you had a blower, that is exactly what you would be doing.