K&N air filter

K&N air filters from Day 1 on every car, truck, ATV, & UTV that I own. Never had a problem. Never noticed any performance increases either. I'll say the same thing about synthetic oil, too. It's a personal choice I've made to use these items and I therefore don't have an alternate reference point for comparison. I feel good about the decision, and that's probably what's most important to me in the long run. On another note, I exclusively run a K&N oil filter on my 1500 5.3L GMC Sierra. As anybody who owns one and changes their own oil will tell you, the filter isn't exactly easy to get on and off due to tight spaces. The K&N filter has a built-in 1" hex nut on the end of it making removal and installation a breeze using a standard socket or wrench.