The gsr induction puts the filter down just behind the front bumper where there is only cold air, the stock filter box sits in the engine bay where there is a big increase in temp from the engine, and we all know the colder the air the more power we create. It's a lot of money but if the temp is lower and enough people buy it I think the reduced price along with some sort of power gain it will be worth it. Don't forget these are normally £203 + postage