@Tron, its ok i anyway i m learning other person perspective on car . But i want to know long time mean how much.. you have read "EPIC" review on TFI i guess, he is driving with Pets box + K&N filter stock from last 80k+ kms .. now i guess he have crossed 1lacks kms in his punto. he have not found any issue using this in long term. i guess 1lack kms its too much time for a car. I personally driven my palio with k&N filter stock more than 12k kms and found nothing, its just give a better air supply to engine when it need the most. you feel very light to paddel your car and its move without issue.