OK, so from what I have heard, read, and now from talking to an Outback Australian dealer, who's words were, if you want to do some serious long distance dirt road rides with river crossings on your AT and with a group of other riders kicking up some dust, then here is my experience on Air Filters.
1. forget OEM and Paper type filters, although very good in dry conditions if you drop it in water and the paper gets wet, then good luck with trying to dry them out.
2. forget Foam, have you seen the size of the surface area on a AT filter? 1mm of dust on such a small area doesn't take long to build up, 2mm thick of dust and it almost goodnight Irene. Foam filters are designed for easy frequent cleaning and you don't want to be doing this on a big long multi day outback ride, especially on the AT and its not so easy to get to filters.
3. use Oiled Pleated cotton filters the like of BMC or K&N, with these he found the best of both worlds, they can be dried out if wet, (it's hard to actually get a oiled filter wet) and the pleated design gives it a far greater surface area than a plain flat Foam one, in fact, he has had a pleated type where the pleat valley's were half full of dust and didn't seem to restrict the breathing. They also don't require cleaning and re-oiling as often as a normal Foam one.
Now, like most of the worlds SUV vehicle owners most AT owners will never venture past a slightly dusty road, let alone a deep river crossing, in that case any of the 3 types will be fine. Whichever sticker looks great on your bike.
Yep, sounds like good advise to me.
