Hi there - a few weeks ago i had my 2004 A4 Avant 190 Quattro remapped with the Revo Stage 1. I'm no expert on these things but apparently it took my car from 190 to 225 bhp.
I only use Shell V Power in the car (From a few weeks before the remap right until now).
The first few weeks the car was totally transformed. Especially in second, third and fifth gear i noticed a massive difference in the powerband. In second and third acceleration was addictive and accompanied by a big whooshing sound.
I was really enjoying a new lease of life for what is quite an old car really.
However from Friday the car seems to have gone back to stock. When I floor it in second and third I do get the sort of whooshing sound but no surge in acceleration. The car also doesn't seem to be driving very smoothly and 'miles left' numbers have plumetted from 420 on a full tank to only 250!