Was close to 90 degrees F where I was at yesterday and I usually find the AC doesn't have to do much. I guess I'll pass final judgement when I'm in the desert heat this summer at 110°F+. Cabin air temperature does not seem like it will be the issue, but the radiant heat from the windshield is definitely there, even at only 80 degrees outside. I'll see what the sunshade does, if I ever get one, and may have to consider adding some additional tinting.