X pipe H pipe or side by side

I asked my exhaust guy, a verrry knowledgable custom exhaust manufacturer and racer, both circle track and strip and this is what he said. The difference between "X" and "H" pipes is where you intend to use them. "X" pipes are more for circle track racing because they scavenge better at higher rpm. "H" pipes scavenge better in lower rpm ranges where torque is more appealing like when launching at the strip. I had him put an "H" in mine.