I'm noticing a difference with v7 HVAC... it's said to be what? 'more efficient' read: "scrimp on power" therefore "less effective". It seems to be taking longer to clear windows at -10C and rear windows never clear. My solution so far, is to put insulation (foil bubble sheet cut to size) up on the inside of the pano glass. This is helping. I have it in rear section of glass, and will be doing front sunroof section next. Hardware fix for a software problem.