I have 7 of these smoke detectors for over a year in operation. Thanks adhesive magnet assembly is easy, and my first 2 smoke detectors were easily damaged because they fell from the ceiling. On the back they are not flat and the adhesive magnets, I had had insufficient adhesion. The bumps are probably structurally necessary to ensure adequate stability when the smoke detector to be mounted directly to the ceiling. So all smoke detectors did back smoothly (with diameter spacers cut) hung and after this experience. I had been 1 false alarm. Why I do not know, because I was on vacation. By pressing the test button, the detector will be probably re-calibrated. Here I was too careless and the detector has well recognized as dust smoke? According to other opinions should be the indicator not possible hang next to electrical equipment (overhead lights), since the magnetic field could also trigger false alarms. These things have I considered in about 30 cm distance. That the detector break when opening the case, I can not confirm. I can recommend the magnets. So you can just take the detector from the ceiling and then open it in equal terms, without standing on a rickety chair maybe. Even if there is an alarm (steam from cooking, etc) so I could already easily jump to the ceiling, grab the indicator on and off directly. It should be noted that the detectors are 100% identical in construction to the HomeMatic detectors. At least I was able to, I ordered here login as normal at the center (CCU2). So I could set that I receive an e-mail that informs me, has triggered which detector.
Conclusion: Pros: Works as expected / design is decent / connection between the detectors is absolutely reliable by Keller, on EC + OG to DG by concrete slabs Con: Can I find anything, so full marks
