Don't know how big it is compared to the Photon but can certainly vouch for the Petzl e-Lite. It is worth every penny and then some.

I have a few of them -- one in my purse, backpack that I bike to work with, car, etc.

And even better testament is that I gave one to a friend for her Himalaya trek (Bhutan)and she loved it.

The 10-year shelf life of those batteries and the incredibly diminutive size of the light make it a fantastic "emergency-light."