Bests & Worsts Reviews from Amazon

August 2019 update: These things are a nightmare. I've had eight units, purchased at different times and installed in different locations, and all except a couple of which give constant false alarms. I have one that won't stop going off until you disconnect power and pull the batteries. Customer support is not helpful and the warranty is a joke. They want you to take the batteries out to "reset it," which doesn't solve the problem. They don't want to replace the unit for you, so I've bought my own replacements and those have problems too. We can't live like this anymore--going to replace them all with a different brand. What a colossal headache (literally) and waste of money and time. August 2018 update: I've had them for a year and a half now. The "fix" described below worked for a few months, but then back to the random false alarms that last about 15 seconds and, of course, always happen in the middle of the night. If one goes, they all go, and at that point no one is going to be able to sleep again for the rest of the night. It's not just one of the units causing problems, either. There's an indicator to tell you which one triggered the alarm. One day it's this one, one day it's that one, etc. I'm going to take them out and install another brand. Update: after a few months, three out of six of these started giving random false alarms. It would go off for about ten seconds, and then stop. A little disruptive in the middle of the night. I talked to their tech support, who walked me through a process of basically rebooting them. It has been about a month since that and there haven't been any more false alarms, but I am still a bit wary. Works great--I've had six installed for months now with no problems or false alarms. Very easy to install. It's nice to have the peace of mind of both types of sensors.