i also use rain X or rain a way all the time on all the glass mirrors included. i made the switch to this w/w fulid
http://www.canadiantire.ca/AST/brows...%252BFluid.jsp a few years back as it adds protection of rain x as you use it, and its in all my autos. it's good to -40c or -40 f. when are temp falls way way down i have to have a min -40 or i end up replaceing the washer tanks and pumps