I have 2 A3's; my daughter's Lava Gray car has 25% all around, with a windshield strip - looks great. My Ibis White car has 3M Crystalline all around - 50 on the Open Sky, 70 on all the windows including the full windshield. I much prefer driving the white car - great visibility, better glare reduction, and equal or better heat rejection. No interior reflections at night. Crystalline or Huper are expensive, but worth it, especially for us geezers with fading eyesight.

 

I did 35% on just the front 2 windows and 20% on rears and trunk. It came out damn good.

 

You should post some pictures!

 

I went with 15% on my dark blue a4 and i love it. It looks really good, and i have no problems seeing out the back window at night.