For several reasons I have 2 chronographs. Someone of less than menses material (aka idiot), shot my Competition Electronics ProChrono Digital. So I replaced it with a Caldwell Ballistic Precision Chronograph Premium Kit. The shooter eventually replaced the CE. Both have their good days & bad. Bright sunlight can affect the accuracy. And having the whole unit down range can be hazardous to the chrono. But in general I have more faith in the numbers from the CE. But don't get me wrong I like (an use) both. The indoor light kit that can with the Caldwell kit works great on either chrono.