Here are my concerns:
- In an emergency, the charge may fail too soon if the flashlights come on automatically. Let's say you leave for work Friday morning at 7:30 am, and your home loses power shortly after. That night you go out to dinner and a movie with a friend right after work. You arrive home at 10:00 pm to a dark house with no working flashlights because these flashlights have already been shining for 14 hours!
- Some of these flashlights take a non-standard battery. You aren't likely to keep a fresh charged one on hand, and you certainly can't store an extra battery with it hanging on the wall.
- Rechargeable batteries don't last infinitely. At some point these batteries will wear down, leaving you with only minutes to a charge. If you don't test the life of your batteries occasionally (And who really does that?), you won't know how long each charge is lasting.
- In an emergency evacuation, such as during flash flooding or a nearby chemical spill, your emergency kit and go-bags are designed to grab and go without thinking. In a rush, you may not remember to add anything not stored with your kit.