This product is reasonably priced and OK. A few design flaws really make it less than functional:First, the power button is impossible to find and use, you need to use your fingernail or a pen to push it in and can't find it when you are driving - which is needed because . . . if you lose signal, which happens very frequently where I live, the unit beeps every 2 seconds with a load and annoying beep and has to be turned off. You just wish the designers would actually try using these products and they might realize the deficiencies.