Bests & Worsts Reviews from Amazon

The long and short: Mount it one foot off the ground pointed towards the tailpipes, and it will work nearly 100% of the time, no matter the temperature or weather. Chamberlain's printed directions want you to mount this sensor four feet off the ground pointed towards the hood of vehicles. However, when we followed Chamberlain's directions, our detection rates were around 50%-60%, with lower vehicles being missed. On rainy or cold days, the detection rate was nearly 0% for any vehicle. We were about to send the sensor back. However, after taking the suggestion of another reviewer here, we mounted it one foot off the ground and pointed it towards the tailpipes, and it has detected flawlessly! It previously would not detect on cold days or rainy days, but now it detects whether rain, shine, or cold. Vehicle size is also no longer an issue since it now detects any size vehicle. Chamberlain should really update their printed directions to reflect this improved method of detection because their four-foot method simply does not work, which leads to many product returns and unhappy customers. It should be a five-star product, but until Chamberlain updates their directions, four stars is all we can give it. Update - 02/07/2018: After almost two years of 10-to-15 detections a day, the original four AA batteries were just recently replaced. In January 2018, the detection rate fell greatly due to multiple below-freezing days and weakened batteries, but a new set of batteries brought it back to full power and consistency. If you need something reliable and long-lasting with minimal maintenance required, this sensor is still an excellent choice. Two years on four AA batteries is remarkable! Update - 10/23/2019: After a cold front moved through and caused the sensor to stop detecting, it was time to replace the batteries for the second time ever. The sensor's internal components are starting to show their age. After an extremely hot and humid summer, the battery pack is warped, which is causing misalignment between the batteries and contacts. In addition, some of the battery pack coils are slightly corroded, and one coil appears to be burned. I scraped off some of the burned debris from the coil, attempted to bend the battery pack into shape, and wrapped the battery pack in packing tape to secure the batteries in it. After playing around with it, the sensor began working again. The sensor is approaching its fourth birthday, and in spite of the battery pack's wear and tear, it is still performing spectacularly well and is still worth purchasing in 2019. Update - 10/11/2020: Now approaching its fifth birthday, I just replaced the sensor's batteries for a third time. After a couple of torrential rain events, the sensor began sending a low battery signal. It held out on low battery for three to four weeks before the batteries completely died. While the battery pack and casing had some moisture in them, the packing tape I wrapped around the battery pack prevented further warping and corrosion. With a fresh set of batteries and new packing tape to keep them in place, the sensor appears to be functional again. I have enjoyed this sensor so much that I purchased two additional sensors earlier this year, though I have only configured one of them so far. Overall, I would still highly recommend this product to anyone with a long driveway or a need to monitor movement on your property.