I've got the Akra Evo with an R3 manifold (also de-cat so in principle should be similar sound levels), sounds properly good but it failed the drive-by at Bedford. Drone isn't too bad and general levels I don't think are too bad at all so was surprised to trip them, there's a remote chance it was induction I guess, but all the chaps on the day said my exhaust was the louder of the 2.