This is a great unit for the price. The "issues" are only a few and only one seriously needing a redesign.1. To ensure it is on is pretty confusing. One "safety" button, a second supposedly to pick broadcast channel that I swear only works in the up position, and a dial that sets level of shock.2. In order to be sure you have actually armed the unit, hold it in your hand prongs up and press the beep button once, and the vibrate button once. If both work you are ready to put it on your dog. NOTE: The intensity dial MUST be on and set to at least one for this to work.3. This is the redesign issue. The remote has a HUGE orange button for shocks. It is clearly just a spring switch and the build quality so low that if you are not careful it can get STUCK ON and you won't notice til your dog goes insane out of pain. Always LOOK AT THE UNIT IF PRESSING THE SHOCK BUTTON AND BE SURE IT DISENGAGES!!!Finally, it is far too easy to accidentally roll the intensity button to increase the shock without realizing.So, for the price it's a deal. If you can't, like me, afford a $150 cost this is a great choice, just BE CAREFUL and keep your mind on your dog's safety.It's a great training tool and is adding much needed discipline to my Belgian Malimois' life.