I wonder if the engine has enough pressure with all those bends and added length. And what about weight, although it will be close to nothing it still hangs after the rear suspension.
Sometimes complex looking exhaust pipework is used to help the airflow of the engine and actually increases power, but this looks cosmetic. I would expect to see something like this on a show car but this doesn't look like a show car to me as it's clearly well used. Odd!