The basic light is very good -- easy to install and use. However, it has two significant problems. First, it does not have an automatic shutoff after a fixed time period, making very easy to leave it on and run down the batteries (which certainly don't "last for years"). Second, and totally unacceptable, is that the batteries (at least on the ones I have) are NOT replaceable. After unsticking the thing from wherever it is mounted (thus marring the surface and destroying the adhesive), you have to unscrew three little screws on the back and pry/push (with some difficulty) the back off. Once inside, you discover that the batteries are moulded into the main body of the device. In short, the design sucks, and this is, essentially a one-use, throwaway item. What were they thinking?!Other than that, Mrs. Lincoln, ....