Pros: Bulb Durability, Battery Life, Durability, Brightness
Color-code your family's emergency kit
In addition to having one on every keychain, I discovered these make great emergency power-outage lights for the family. We hang them on lanyards, and when we lose power in winter storms, the light hanging around your neck shines a pool of light right in front of your feet so you can see where to step. Having them in multiple colors meant we could color-code the kids -- they liked the variety, but their mom and I knew who was at the end of the hall or coming down the stairs by the color of their flashlight. (We really know how to have a good time in a power outage. We're just cool that way.) Additionally, the orange and red lights make it easier for your eyes to adjust to the dark. They're also great back stage (two of the kids were in theater in high school, one in tech), where the red doesn't show up if you're reading cues or reaching for a prop to hand to an actor.