This is only my opinion but if you are only going for improved airflow then a panel filter replacement such as K and N or Pipercross is perfectly sufficient. If you are just after a bit more noise then an induction kit (replacing the airfilter housing etc) will certainly give you that. Would you notice any real improvement in performance? IMHO not really. I have a K and N panel filter but only because it was gifted to me. I didnt see any real improvement. Anything i a changes i thought i could feel were probably in my mind. In conjuction with other mods it most certainly will help.