X & H pipe vs straight dual exhaust

The X is better for scavenging at higher RPM's, and ANY type crossover from one side of the exhaust to the other is going to quiet down the exhaust by partially canceling out the harmonics created by each cylinder firing down a single pipe.
I did a crapload of reading on the differences before I did my 2.5 inch X system.
And as said above, it does create a different sounding exhaust.