As Bob said, without proper headers there is not much of a gain, our exhausts are pretty good from the factory, its not about being rich or poor its about being smart, many have tried and spent much money on there exhausts with minimal to no gains.
If you think its due to "poverty" that he just got a "muffler" then your insulting a large portion of the community here as I know MANY members only have just a "muffler".
and I hardly think you should be speaking about money when you think $300 is to much to spend on a quality Mercedes engine