Since nobody has mentioned this one yet, I'll tell you my favorite is the M Performance. I've had the E.Race and AA and have heard the Akra Evo. The E.Race is my favorite sound wise but it drones, as does the AA. I'm not a fan of the Akra tone. The M Perf is the exhaust I'm happiest with right now. Light weight, looks great to me, absolutely no drone and sounds awesome and yes it's got balls...literally. Just paint those sucka's!