Nitrogen filled tires take longer to heat up (good for hot places) When pure nitrogen is used, the longevity of the tire can improve up to 75%, since there is no oxygen, moisture, etc. to ware the rubber.... you also get a more even tread ware since it's a pure gas. Though our air is 78% nitrogen, those other elements make all the difference.... Just like adding a little bit of salt to boiling water! If you live near a costco, they usually keep an airhose outside of the garage hooked up to a nitrogen tank so people can fill up with n2 rather than putting normal air (normal air mixed with n2 will cause an imbalance in the tire, so it's mandatory they leave the hose out) So go get some N2 for free!! Just go afterhours!