The heat-gain in this area during the summer is crazy. We routinely get into the triple digits with variable humidity levels and lots of sunshine. The hardest the A/C has to work is when it's over 100 and the humidity is low, vent temps matter! Ceramic window tint helps a LOT, but I haven't yet done it to my 350SD. Despite that, it still has one of the best A/Cs of any car I have access to.