Thrush glass pack or Flowmaster?

[DaFinksta]

I was talking to a friend who has a Thrush glass pack on his TJ and he said I wont get any more power if I go with a Flowmaster and also the glass pack is cheaper. Is this true? If I go with the glass pack, will I see the same or near the same results as if I went with a 2.5" Flowmaster 40 series? I really like the way his sounds with his glass pack, but I will sacrafice the sound and money if I can get more power with a Flowmaster. Thanks a lot.

[fireisfun]

Flowmasters will NOT give you more power. Just sound. The idea of performance exhaust is to let more exhaust gases out. The flowmasters inverted design will never let as much out as easily as a flow-through muffler. Basically the glass pack will give you more power. Go with the glass pack or another brand of muffler (ie: Magnaflow). Keep in mind though that if your truck still has the stock exhaust system the benefits of just an aftermarket muffler are going to be minimal.