a 16g is a great turbo. Many people have run 11s on a 16g. in full weight cars. Not to mention there is MUCH less custom work to be done when you switch to a 16g as compared to a 20g. Some people like the simple swap or dont have the know-how to do the custom work. Keep in mind there is a price difference too. Not just in the turbo, but in the different intake and IC piping. You might need to upgrade your fuel system and other engine components that you would not have to upgrade if you go with a 16g.