Yes, I ride with the stock mirrors vertical for better visibility, but I mostly use the bar end mirror to see behind me. I am tempted to get another bar end mirror for the right hand side and remove the stock mirrors.
I spent over an hour cleaning off the dust, sand and salt that I picked up on this weekend's rides. When it snows around here, there is a ton of sand and salt put down on the roads to prevent cars from skidding on snow and ice.
