Umm there's only one type of mylar that comes in various thicknesses.

It is the kind with a mirror type finish.

I would either go with the panda film (black and white poly vinyl) or just paint the walls flat white.

Mylar is slightly more reflective than flat white paint but creates hot spots, is a pain to hang, tears easily, scuffs easily, and very hard to clean unlike flat white paint, which is much cheaper to boot.

:thumbsup: