I've had this Fluke NC tester for several years really like it. It's by far the best of the non-contact voltage testers that I've tried. I use it all the time for simple go-no-go voltage checks on receptacles outlets. You have to be careful with it just as with any of these type of NC testers, because they can give erroneous results under some conditions, but sometimes there is just no way to gain access to physically connect test leads from a multimeter to the wiring, such as when several spliced NM cables located in a damp crawl space are enclosed in a metal junction box that has the cover fused in place and is completely encrusted with rust and corrosion, so using a non-contact voltage tester is really the only way to verify that the circuit is disconnected. In a situation like that, you really do trust your life to the NC tester and I have had to do it in more than once in the past. You would always want to verify that the voltage is off with an actual meter whenever possible, but in bad situation like I described, I know that I can rely on this Fluke NC tester until I can otherwise access and test the circuit. I've owned a couple of different model Greenlee NC testers previously, but didn't like how the batteries in them always seemed loose and would rattle around inside, so that is what initially made me switch. I now have two of these Fluke 1AC-A1-II testers and always carry one of them in my tool pouch with me at all times.