Do a search on exhaust. This has gone around a number of times.
Remember the reason for the x-pipe in the first place. This was designed for the V-8's because of the "Unsynchronized†exhaust pulses that create additional turbulence in the exhaust path. The original idea before the x-pipe was the crossover. This crossover was installed in dual exhaust setups to disrupt the flow at the point of the hot-spot created by this added turbulence. Years ago we use to install our pipe and paint them with white paint. After a quick trip down the freeway and back to the shop, you could see the dark brown spot on each of the two runners of the pipe. It was a simple matter of connecting the two hot spots with the crossover pipe. Come to think of it I have never seen any test results that showed an improvement by installing the crossover.
The x-pipe was developed for the same reason and is also believed to have a scavenging effect due to the exhaust path from each side passing the other open pipe. I haven’t seen any result of testing that proves this actually works either.
The 200 has a full 180 degree firing order. This allows for equally spaced exhaust pulses within the full length of the pipe. Short of normal turbulence that is seen with the flow any material down a pipe, the 180 degree firing order is the best start for any engine to increase the efficiency of the exhaust. I have always promoted the elimination of crossovers in the exhaust pipe out of the dual exhaust headers for the inlines. I would be afraid of actual creating additional turbulence from what would already be evenly spaced exhaust pulses.
Keep it simple, and have fun. Ric.