Pros: Every drop something in movie theater? Need to find the keyhole in the dark? These lights are so strong that it practically lights up a room, enough to find whatever you are looking for. Battery life is pretty long and these things are so bright that it hurts my eyes looking at the LED directly.
Cons: My only problem is the flimsy On-Off Switch. There is a temporary on-off and a permanent one. On some flashlights, the permanent ones makes it flicker. However, temporary on-off is perfect on all.
Other Thoughts: At $.47 each, these are a steal! Building these yourselves would cost more because the LEDs are so bright.
Bottomline: Buy them now! Great gift item for friends and family. These things are about $5 each in the U.S.A. $.47 each is a steal. You would probably use these for short periods of time so the flickering I noticed on permanent some flashlights don't matter, since you would probably use the temporary press switch.