Well, I've had mine for about 9 or 10 months. My opinion is: I'm happy with my unit. For the $50 or so dollars I spent it's well worth the $$. I do get a false reading out of one sensor when I put the truck into reverse. However, I found that if ONLY one sensor is picking something up there's nothing there. I've never had a false reading when it counts
Lastly, I fall into the catagory of: small dent on the drivers side rear bumper.

Happened before I got the sensors