I agree. In fact short of some extensive testing to prove it I believe the x-pipe will actually hurt the performance of flow thru the full length of the pipe.
The Inline has a true 180 degree firing order. With all things being equal (collector lengths), the exhaust pulse thru the pipe will be evenly spaced until there is a disruption in the pipe like the X.
It is cheaper to leave it out as well.
Good luck, Ric.
