Highly recommended! Very discreet. Very loud. Not flashing disturbing.

Have our house equipped with smoke detectors and chose models with 10 year batteries, now that I have heard often how annoying it is (at the cheap), when a battery is empty and you have to hunt through the house again and again to the respective find troublemaker.
And I came across the two test winners met in the same price segment:
Since the ST-620 DET for a lot more sophisticated / discreet looks and also not optically but also detected nor thermally I bought these for the living room, office, hallway and basement. As disadvantage I felt (unfortunately) in advance that these flashes and therefore ordered some egg Electronics 10 year smoke alarms with lithium battery for the bedroom. After a few weeks in operation, I can only say that the blinking did not fall on. My husband had the highest concern that the flash would but also interfere with the television, when I told him before the installation that the smoke alarm would flash in the living room. Both we did not thought about it, and just last week I noticed that I never looked one of the ST-620 flash conscious.
If I had known this I would have the whole house equipped with this smoke alarm.
Especially since we noticed during testing that the ST-620 is significantly louder than the Ei Electronics, although both manufacturers 85dB is specified.
Even Super: 10-year warranty (Ei Electronics is only 5)