I have the gen 2 K&N kit on my 180 and tbh the only difference is the noise, i like to hear the KV6 breathe when stretching its legs, as for fuel usage no diff at all. Power gains ? well realistically it isn't going to make a sausage of difference in general driving because with the VIS motors on our cars there is no way of guaranteeing that they are opening fast enough, far enough etc etc so a couple of bhp either way is nothing * this is only my opinion after having 2 190's and now a 180 with the K&N *
Saying that on a nice freezing day there seems to be a tiny bit more mid range grunt but again that could just be the ECU adjusting to air temp.
Simply put IMO if you want a nice induction sound for day to day driving the Induction kit is the way to go, If you want quiet performance on a race track the panel filters seem to be popular for this.
