I asked my dealer about the K&N filter as well. He said the same thing; the bike is well tuned for the stock filter. (got to agree :rockon:)
But, I did put the K&N in my 2009 Sienna van. It added pick up, and ~1mpg better average gas mileage.
My post was about engine oil. I have a new bike with rough shifting, they said that with every oil change it should get better. Mine shifts a little rough up-shifting in 4th and 5th. Yours has more miles, may have been sitting a while, or got some bad juice??