What is it about this pipe that makes it flow better than others? I've heard a lot about it lately on the board and i'm just wondering how much better is it than the rest. I'm getting ready to install a BBK o/r x on my car. HOw much better is the Dr. Gas? how much does dr. gas cost??

if you look at BBK, Bassani, Magnaflow and SLP you notice the X is far away.
its my favorite exhaust.