Cheers Cuppa, I took the test on the 2T and the results were instant as far as driving through the seat of your bum, it felt like an anchor had been removed from the towbar within about 5km of the Servo. Cant notice any difference in economy but start up is a pleasant noise. Another bloke with a similar rig tried it after and agreed that things felt as if they freed up.
cheers
Mingo