Fram has good quality stuff. Purolator and cheaper price stuff is the opposite. I bought Purolator oil & air filter several times over the year because I was to lazy to goto a farther store to get Fram in which all resulted in bad experience and fast replacement..........oil filter has different standard size.....one air filter does not fit and I did get the right #and size..........another air filter crack open on the side.......don't know how many road dust and bug my engine had combust...........avoid Purolator and cheaper stuff.
truthfully, In my honest opinion. K&N is the absolute best that you can get. The fliters provide by far the best flow. They also have a Million-mile warranty, and they can be washed and reused over and over again. I like the one i have in my Sentra so much that we got one for our Plymoth Voyager as well.
If your looking for something else thats not K&N, ive heard that some people have had good results with "American Products Company" (APC). They have intimidator intakes i think. From what i hear, the filters are pretty good. I have no experience with them myself, so i dont really know though.
Be carefull when choosing a filter. Ones that are made of paper, and oil saturated foam, provide terrible flow, less than impressive durability, and dont filter very well.