Although my personal preference is to the KE exhaust, since you mentioned "bang for the buck", I would have to agree with many on this thread. The Stainless Marine cast exhaust should be your choice.
I did a fair amount of research before choosing the exhaust for my 502 and the Stainless unit is a stout piece.
Forget about your budget line and just go out and shop your best price. In 5 years you will be thanking yourself (length of the warranty period).