Don't get either of those on mine Steve, just a bit deeper growl more like original m3 exhaust, when they fitted mine they hadn't done more than about 3 others and were keen to see what they could achieve with different sliencers, did give the fitter a good drink though, oh the tail pipes are Power Flow and my choice, hope they still do em for you, the only problem I've had is the tails moving over to the N/S ( which is natural on a straight six BMW ) so you might ask the fitter if it's likely to move enough to burn the bumper cutout which it did on mine, maybe they can compensate for this when fitting. Good luck Roy.