From FHEM surface of the dimming actuator can be dimmed any (I use 3x 4.5 watts dimmable LEDs), there are settings possible from 1% to 100%. However, when dimmed over the wall switch, the actuator switches off completely rather early (bez. Late one), so you do not come down under 15% (felt). I think that's a shame, because I want these settings have a look, for example, to watch TV just like. Currently I use the smart phone on hand to herunterzudimmen the light when I want it as dark. Because of this limitation, I prefer from 1 star in rating.
It should be emphasized that the dimmer copes well with the low wattage of the LEDs. Previously, I had an older dimmer the LEDs could not turn down so far.