Its awesome and extremely easy to use. Just take it out of the box and plug it into your OBD port start your engine and drive. Unit emits a cool looking cobalt blue light when engine is on. Ive had mine for about 3 weeks. I never unplug it. Ive had no battery issues. You can unplug it and it will not damage the engine. Engine will go back to AFM mode. Im very happy with it. The AFM was driving me crazy.