These would not be the best bright light for lighting a room, but we love them in our bedroom for a nice soft yellow light when powering down for sleep. Nice ambiance. I would get a brighter white for power outages.... The bright white ones were too blinding for everyday use "powering down" but these are just right. We use two in a large bedroom approx. 16' x 16'. Can see well to get around. These along with the brighter ones were a lifesaver when the lights went out here in TX for three straight days last winter. My grown kids thought I was crazy when I heped Santa and put them in their Christmas stockings - but shortly thereafter I got several calls from all 4 sons telling me how brilliant it was Can't have enough around! We walked all over the dark house with them.

I bought these to do two things. First I placed two in a Tuffy security box I installed in the rear of my soft top Jeep. The box is secured by closing the tailgate so the overhead lights no longer illuminate the rear cargo area inside the box. I ran across these and thought they may be just the thing I needed, and I think I was right. I mounted one on each side and they light the box up great. The pics are taken without a flash and minimal surrounding light at night. The dark one shows more than I could actually see with the naked eye. I am very happy. I also like that being stuck with a magnet I can simply move them wherever I may need them. I do wish the magnet was a bit stronger but I do not believe they were ever intended to be in the back of a Jeep so for their intended purpose they are more than adequate. I can always add a stronger magnet. That said they have not slid or fallen with regular driving but I'm sure during off road driving they may. I'm not knocking them as they can be mounted others ways if this becomes an issue. I really don't think it will though. I can deal with them sliding down the wall a bit the few times I may go off road to keep their versatility.

The second was to place in my locker at work. It worked wonderfuly and I can now easily see my gear with a simple touch.

I also really like that they are activated by a simple touch. No push or click, just a simple touch. Then to dim or brighten you just continue to touch them. Very simple and works great. I would buy them again.

UPDATE 3/2018
so after my earlier review the company emailed me asking if it was okay to send me replacement free of charge (i previously found I had 1 bad one in the batch 3). I said yes of course and lo and behold i received not 1, but a box of 3 today! anyway kudos for excellent communication and followup, the company obviously cares enough about their reputation to provide the 'extra' service when needed. changing my rating to 5 stars for great product and service
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I have bought several stick on lights thru amazon over the years for my little guy who doesn't like sleeping in the dark, they all eventually went into the wastebin due to shoddy workmanship and high battery drainage. I am please to say this item is quite different.
Pros
-very thin and solidly built, I can honestly say these stick on lights are of higher quality from the way the battery cover twists off smoothly to the sensor light transitions from bright to dimmer with a finger/palm touch. Other lights I have purchased, the cheap plastic stays eventually break off due to the constant replacement of batteries (every morning)
- battery life is Great! my little guy leaves the light on dim all night until the morning for the past 10 days, still working fine, no battery change yet
-bright enough for a dark bedroom with a dimming function, I can't speak about other spaces such as a closet but this was more than sufficient light for my purposes, such as reading a bedtime story
-3m sticker with the metal circle allowed me to place it anywhere on my wall, since the base is strongly magnetic it holds very well
Cons
-not much except for the fact the 3rd light (it came as a set of 3) does not work at all hence the 3 star review, otherwise I would have given it 5 stars
I won't be returning them as my son loves his new light (you have to return the entire set and i didn't want to deprive him) so 5 stars for the two lights that work, but a 3 star review for the entire set (heh, 2/3rds of 5 is about 3 stars which is equivalent to what i got)

First thing- this is a pretty good value for what you're getting.

They work fairly intuitively, and they give you lots of ways to attach them (magnets, sticky tape, even screws). The touch functionality works well: click and hold it down to make it brighter. Click and hold to make it dim. Push to turn on or off. Does what it claims to, and I'm happy about that.

There is no motion activation function. That's not a thing with this.

I use this for the baby changing station- just put it above the station and tap it to have whatever light you like. It remembers your last setting, so you dim it to what you like once and it'll keep that every time.

I also put them in the pill drawer and the bathroom so that I can have juuuust enough light when I need it.

So I think you should purchase this. Let it be a light in the darkness when all other lights go out.

I use this to light my nightstand drawer so I can grab medications, etc in dark conditions. Once I was able to get it to the dimmer mode, it works like a charm. The touch technology is easy and reliable. The dim setting is just enough light to for me to locate the items I need with being too bright. Still not sure how to switch between these brightness modes. I had notions of using this to light a closet without electricity. However one puck, even on the brighter setting, wasn't enough light to cut it. I'd need to use multiple pucks and I can't readily do this because the closet walls are old plaster, not conducive to adhering the double sided tape which secures the pucks. Plus, I'm just not in to tapping multiple lights each time I visit the closet.
I've been happy with the battery life. I've accidentally left one of these on (8+ hours) a couple of times and I haven't noticed a decline in brightness.
This concept is a nifty idea. Pucks adhere just fine in most locations, I just have a very old house. I like this for little spaces but would look for a larger option to light an entire closet.