The Proton is an interesting light in my collection. I have several more sophisticated and brighter lights, however, the Proton remains my EDC work light and lives clipped inside my back pocket. It is the combination of readily available battery, although I generally use eneloops, the size, and narrow spot beam that keep this light #1 for my daily use.
It is not a throw monster as the reviews and tests will tell you. The beam is ringy if you are a white wall hunter but in practical use it has never been an issue for me. BTW, I like that the light comes on full bright. I believe that the design intent would be that if you are worried about your night vision then the red LED should be used which does come on low first.
Later,
HB