To calculate the overall star rating and percentage breakdown by star, we do not use a simple average. Instead, our system considers things like how recent a review is and if the reviewer bought the item on Amazon. It also analyses reviews to verify trustworthiness.
I purchased two of these units the first one worked OK. The second one has a problem. In a side by side comparison the signal qualities of the two units vary. I checked there accuracy and tracking with OziExplorer moving map software. The first unit tracks pretty good, but the second units position is off a large percentage of the time and sometimes as much as 400 meters. I sent the faulty unit to Garmin to be repaired. They sent it back with a description of the problem and that it had been fixed. I checked the unit out and it is the same as when I sent it to them. Now I'm stuck with a dud.