I put 230 miles on mine so far and i live in the UP of MI and like anyone here will tell you its DUSTY. Now i have to admit i havent had any dust that i can tell thats gone into my motor. I checked it frequently cleaned the prefilter and greased the seal on the lid every time I opened it. At about a 150 miles the dealer installed the flexable boot. I guess im a more leary person them most but last week i ordered a DF air box and clutch kit. Ive studied all the razor forms closely and have yet to here of anyone not pleased with the df box and for the extra 100 bucks over the ump im not going to loose sleep over. Im also not going to take a chance on a vehicle i have over 15 grand into because im to cheap to buck up for a 500 dollar intake. It was my money and i DID spend it and will never regret it. I dont want to be driving down a dusty trail or following a buddy kicking up dust and worry that im sucking sand! Ive got two people in this small town that have been running rzrs for a couple years and both have had to have there motors rebuilt and ones on his second rebuilt. So the problem is REAL. Ignore it and it isnt going away.