Bests & Worsts Reviews from Amazon

I bought 6 of these from Amazon. After about 3 years, one started to go off like there's a fire when there wasn't. I bought another one to replace it just to save the hassle of mounting a new bracket. Then one by they all started doing the same thing, going off when there was no smoke or fire whatsoever. I kept replacing them with the same unit out of laziness. So far 4 out of the 6 original have been replaced. I'm should have switched to some other brand sooner. Today I got rid of all of them.