Bill,
I dont have the one you mentioned, but I do have the Vital Bow Proslide which is the single vertical pin type. I can say that its one of the brightest that I had seen and works great! However, you are right about the markings, or lack of....... that would be a good addition.

I had it in my case which was slightly open when my wife saw it and told me that I left the light on and had better turn it off before the battery drained I had to explain that it didnt have a battery!

Keith