To clean the filter is no big deal. I wouldnt replace one cotton filter with another. The difference is minimal, and IMO would just be a waste of money.
To clean the cotton filters, generally i clean mine every 5 oil changes, or 30K miles. Just remove the filter, and spray on the oil fliter cleaner and let sit for 15 minutes. Then with a garden hose on gentle pressure ( too much will force the cotton guaze out ) rinse from the inside out, the reverse of the air flow. Once all the air filter oil is removed, the filter will be white. Let dry naturally; sit in the sun for about 15 minutes. Apply fresh coat of filter oil. Here again, i cant see the difference in a cleaning kit, they are all basically the same. K&N is a red oil, and the AEM is a blue oil i believe.
i remember a while back that K&N filters were used for AEM intake systems. this is what i saw on a 2000 Si. i beleve it even said K&N. sometimes its marketing. like the lexus emblems on toyota engines. that type of thing. the K&N design is pattented so other corporations can only mimic the design but not be excatly infracting the patent/design of K&N
i guess they worked out some deal
07 VW GTI DSG
07 Tacoma X-Runner (gone)
04 BCP xB 5-Speed (died)
3/10/04 to 12/10/09. May she idle in peace.
Reppin' the 910, 919 & 845
Oh and normal cleaning interval for these things are along the lines of a regular air filter element , or about 30k or less depending upon how dirty the roads are where ya live , and the intake systems filter placement.