What are the bad effects of photogray glasses for sensitive eyes?

Not as effective yet: Transitions lenses (photogray, or photochromic) are not polarized. If you wear photogray prescription eyeglasses and you are light sensitive, the lenses will not reduce the hard glare. Photogray lenses are less effective in hot weather and in some cars. The manufacturers are working on improving them. For now, I would recommend that you get sunglasses until the technology improves.

Sunglasses needed: Photograys can not replace sunglasses in strong light conditions - they are not usually dark enough and allow light into the periphery (from both front and sides). The photogrey effect can also be canceled by your windshield tinting - leaving you unprotected from bright light in the car. Some artificial lighting also triggers the photogrey effect indoors, making it difficult to see.