Today was a cloudless day where I live 4 hours north of Toronto. Sure it may not be a summer sun but it was darn hot on the face and very bright.
I sat outside and read for about an hour no problem... well had to turn the brightness to either half way or Auto. Inside I use it on lowest setting even during the day it is just so bright.
I will say it makes a nice mirror outside so you have to find the right angle sort of facing up and all is good.
I still have the protective cover on that it shipped with. I peeled it halfway back and the glass was still a mirror if held like you would read a book or look in a mirror. Amazed they can't use a kind of invisible glass like they have for art work that has almost zero reflection from it.
Sensitivity is amazing but I am not sure if it has to do with dry air here this time of year enhancing the charge from the skin or maybe just my energy