As the title really is anyone running a 3" downpipe with fitting a lower mount insert? I fitted the powerflex yellow one the other day and now done 150 miles hoping it would bed in but its unbearable. Best way of describing it is the car feels like its got a misfire up to about 3k! The manoeuvring part with extra vibration I expected but not on the move. I've tried various tightening torques which made little difference so I think I'm going to remove it and try running my downpipe without one. Anyone any suggestions?