Well, we are heading into our first winter season here in the far NW with our beautiful P85+. Had the 21" Turbine's switched out for 19" Turbine's and WOW are they ever quiet!! The 21's are fitted with PS2's and the 19's are set up with Primacy MXM4's. The road noise is very reduced with the Primacy's, even the chewed up from stupid studded tires pavement around here is way quieter. Went up to Artists Point yesterday and could not believe how quiet it was. Any one else have this experience?? Thought the 21's were quiet, but then the switch, wow.