We have used "Prompt Sunscreens" for 9 years on the outside of the our front window. We can feel the difference of heat by putting our hand on the window before attaching the sunscreen and after attaching. There definitely is a big difference.
We much prefer to see outside during the day. We have been in RVs with a white or beige outside sunscreen and those with brown or black. It's amazing the difference in seeing out. With the dark colors you can see crisp images at a further distance than with a light fabric. We chose dark brown wich coordinates well with the motorhome.
Of course, our first choice is to park on sites that face north. That's the best. :)
