Even i was planning to add a sunfilm for my windshield? Do you feel any improvement after having the sunfilm? Any difficulty in night driving?
The 70% vlt from 3m works great for the front windshield(please dont go any darker),you obviously need good visibility to drive that is the first rule remember I had different cars for day & night(you mite find it weird).
I have driven cars of every make with different front tints from innova,octavia,cruz to audi,merc,bmw & I have found silver(reflective) or moss green tints(rare now days) for the front windshield to be the most effective(considering privacy & night visibility).
I will tell you when charcoal tint front windshield tint takes the most toll on your visibility! If your in a city & have good street lights around you dont feel the effects,but when you hit the highway I have noticed with high beams hitting you it becomes a prob to scan the road for defects like pot holes or debris,but that is not the worst when it rains you mite as well crawl at 40,I have changed my charcoal front tints twice & finally taken it out when I could not resist crossing 120 at night drives(occasional then,regular now),I have almost hit fallen branches during rain inside the city(my vision is excellent) & my friends innova clipped a divider when he had charcoal tint,after shifting to reflective shades the night prob is reduced.
Front sunfilms cuts out alot of heat,but you have clear films too if you are worried about visibility,if you have Hid high beams then charcoal front tint can be a disaster at night(experience from using tinted Audi Q5).
My final opinion is go for reflective front tints if you cant cut for an expensive clear V-Kool(no privacy though),you mite have reflection of your dash board during the day but a safer option for the night(unless you drive with your interior lights on)
Hope I have helped you guys from my experience!
These are my personal experiences & I do not want to oppose anyones views on this forum & all the tints I told you about were genuine not counterfeit as mostly used by some car showrooms & car accessory shops (please be careful).