At this point and until I here your reviews the thing I can't do without is a visor also, I love the mission, it's warm and quiet. Until the Mission came out I thought I would never leave the Arctic Cat TXi Helmet w/ Electric Shield.
I completely understand! The Mission was my first choice, but I decided to take a chance. I know so many people who like the Mission and nobody who doesn't. The 509 is an unknown, and that's why I ultimately decided to try it. I'm planning to share whatever I find out, so hopefully we'll all learn together.