friend of mine just had his glass up top tinted and it helped a lot.Hmmm as a 2020 M3 owner, the main thing for me would be the darker glass on the roof. Living in Texas I have to keep sun shades bought off of Amazon up for 1/2 of the year. They make a huge difference in cabin temp. I also would love to see cooled seats, not just heated. More applicable in hot climates.