It is Hot, but definitely nothing close to the temperature in a
Oven. Dark film doesn't really helps in heat reduction, or should I
say the reduction isn't measured by how dark the film is. V-cool
has a package that uses clear film and it works.
As for the heat, leather seats tends to be a lot hotter. Shade is a
big help since it is because of the greehouse effect that is
causing the heat, not the temperature of the surrounding.