Power Tuner for Gas engines

The K&N Cold Air Intake was put on around 20k miles. I paid $100 for it, a friend took it off his X when he traded it in. the 4.30`s were done around 25k miles. Can`t really say the K&N gave me more power, I believe it does, but I bought it so I don`t have to buy anymore filters. the biggest difference was with the swap from 3.73`s to 4.30`s....money very well spent. I did the tuner and Y-pipe this spring. I paid $500 for them from 5 star tuning. the tuner alone was around $400 I think. the tuner adds around 20HP when in the towing tune. but the biggest gain was from the transmission shifting strategy! the Ford trans is a dog in stock tune. the tuner allows the engine to better use it`s powerband/torque curve! I`m very happy with it. with everything together the Excursion is now a beast of a TV and will do whatever I ask of it! 5 star tuning asked me when I ordered the tuner what mods I had done to it, so they must need to know something when making the tune for my specific truck.