When you have a bike that is as light weight as the new FZ 09, mass centralization becomes very important. Usually, the Cat and the muffler are quite heavy and to have that mass centrally located and under the bike to help maintain a low center of gravity will definitely contribute towards the bike being very flickable. I have had several CBRs....a couple of the 1000RRs, and two of the 600RRs, where the exhaust is up under the rear tail section. They tend to make the bikes a bit top heavy when compared to the type exhaust that the FZ 09 and the newer 1000RR have. I like it for both; the reason mentioned above and the looks of it.