I looked in to this myself a few weeks ago and the pipes are that length and shape for a reason, it's all to do with the way the air flows. You may find a drop in power and torque if you change it. The 1.8T engins the air is forced so it doesnt mater.
Sorry i can't exsplane it better, but i would read up on it first before changing it or atleast get the car RR before and after to see.