Topic: Baffling methods...which to use for what purpose?

[RFogelsong]

So I've seen a number of different ways to baffle pipes, fiberglass/steel wool, mechanically (make the gas turn corners and such inside the pipe), those perforated metal inserts...

Which is "best", or maybe, does each type give a distinct sound or why isn't everyone using the same method? 

[Don R]

It's usually a packaging problem. A baffled system works well but it needs a large area to fit in to be quiet. Many muffler cases are tapered, that's a concern too. I prefer a large dia. can with a glasspack insert.