Be careful with the Polaroids. Seem to remember some info some time back back warning against the use of polaroids for flying due to the fact that they do not stop UV rays. Because of the reduced light to the pupils your pupils will enlarge, allowing even more of the UV in, with possible long term harm.
Also, as someone has suggested, the wraparounds are better. Non wraparounds will cut the forward light to the pupil but the light from the side will still keep the total light at a high level, keeping the pupil small and making it very difficult to see inside the cockpit. The wraparounds cut the total light, allowing the pupils to enlarge and greatly improving the view inside as well as out.
You can try this out simply by placing your hands at the side of your current sunnies.