You don't need to spend money for window tinting if you are doing it for skin cancer prevention. The glass alone does that pretty well. Tint improves this only slightly.
In my research Opticool Pilkington glass is pretty good at keeping out the heat. I had originally intended tinting my D4 as I had done many of my previous cars. I haven't yet because this car just doesn't seem to need it.
Perhaps it cools quickly with rear air con, but what ever the answer, my D4 does not seem any hotter than my previous tinted Navara or XJ8 Jag or VW Eos.
My conclusion: Tinting is really for looks. Spend your money on something else.

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