a lot of people are gonna tell you to get the name brand full exhaust system like Greddy, coz they sound better, look better and will gain "A FEW PONIES" compared to just a muffler only.
the only thing i hate about the full exhaust system is they cost a lot of money. im talking from $400 and up to get a good exhaust system to get "A FEW PONIES".
So, if you want to spend hundreds and hundreds of dollars to get "A FEW PONIES"( maybe 3-8 hp) and claim you have a name brand exhaust system, go ahead.
but if you want to save money and get a pretty decent muffler only(too many to choose from), and you might get 1,2,3,4 or maybe 5 hp. a lot of them will not sound so nice but if you im pretty sure you can find one that has a deep sound and one that suits you.