We have performed both Stage 1 and Stage 2 on a number of 1's and 3's and I can say this is one of the most noticeable tunes I have ever installed! Absolutely incredible client feedback. My last client(2011 128i) did not even get down the road out of my sight and he was calling me asking if I did more performance mods that I did not tell him about. Worth every penny for the changes to the Valvetronic engine! Nice work AA!