What's the main difference between flowmaster and pypes dual ehaust. i've heard they're both good. which give better sound and more power in your opinions?

 

in my opinion you need to open up the heads and intake before you think about exhaust, because that will make alot more power. but i would gho with JBA shorties and the pypes exhaust. the flowmaster is a y-pipe setup and is not true duals, the pypes exhaust is.