I got two at the same time, maybe three years ago now. I put one in one tank, and the other in my other tank. One tank has run flawlessly, can't fault the inkbird in this tank at all. The other tank is now running with no inkbird at all, i'm just relying on the thermostats on the heaters. The reason being is that I had no end of problems with the inkbird on my second tank. I even replaced the faulty inkbird with another new one and before long that one started playing up too.
So it's pretty much a mixed review from me, and from what i've read on previous posts over the months a lot of people have had similar experiences to me. They can be very good but also very bad if you're unlucky.