I have used these, and they work great. You need to know that they put out a very narrow beam of light, which is very effective for lighting individual props. Sometimes you need to use more than one on a prop. You can create some really neat lighting effects by lighting 1 side of a prop with 1 color and the other side with another color. 1 power supply can usually power a whole bunch of these at the same time. You can easily buy wire to extend the cords as needed. You just have to make sure you attach the positive to positive and the negative to negative, otherwise it won't light. It won't hurt it, it just won't light. As you probably know, LED stands for light-emitting diode. A diode is an electronic component that only allows electricity to flow in 1 direction. So if you reverse the polarity, it won't light because it is doing what it is designed to do... prevent electricity from flowng in the opposite direction.
Anyway, give them a shot, I think you'll like them. Just remember that they won't put out a lot of light. They are perfect for focused light on a single prop where you don't want light to bleed onto the ground or other props like a flood light will.
