cross pipe section on stock exhausts

are they necessary? all the aftermarket 2-1s I have seen do not have this setup. would it be ok to cut it off and patch up the 2-1s? pros, cons?

The cross pipe on the stock dual pipe setups increases low RPM torque. You can run without it if you have to.

If you'll look at the stock exhaust system, you'll see that the pipes are rather narrow after the cross-over pipe. By removing & plugging the cross-over you'll reduce the exhaust outlet by half.