Product review (4 stars): Works like a charm
Bought this to add to an existing setup.  I've already got one of this switches by the bedroom door to control the lamps.  Just needed a second switch to go by the bed. Just match up the dial settings and it was off and working.

The battery it came with was dead.  Keep in mind this uses a special 12V battery that looks like a stunted AAA battery.  They're about $4 at an electronics store. The battery tray isn't well built so the battery has a tendency to fall out whenever you remove the baseplate from the faceplate.