I've readup on owners experience with VAG 1.8T remaps. Some are getting 20mpg as the power comes in much lower and lots more of it and others are getting similar or better than standard.
It depends on how much you are pushing the envelope with the remap. It is probably more noticable on a petrol than on a diesel.
Why should you let the garage use the full power of your engine - switch it to valet mode and stop the little joyriding grease monkeys from destroying your diff
