HMistica,
You'll find they are all very close in total volume, one thing you didn't mention was what year truck you had, if you have a 2004. 5 and want it loud you'll need to remove the cat as it is a pretty good muffler all by itself etc.
The MBRP is what we are familliar with, they are available in aluminized 409 and 304 stainless. Duals and singles etc.
Mark @ DPPI