Appears these are only for incandescent bulbs and not the newer dimmers that handle CFL or dimmable LED.
They will still work for both.
The 4-level dimmer is great for the bathroom. If you wake up in the middle of the night and have to go, you can turn the lights on at 25% instead of being blinding by 100% light via a regular switch.
Also, the low voltage dimmers are only for 12 volt lighting.
From experience, not well for dimmable CFLs, but acceptable for LEDs. With CFLs, we had a very similar dimmer to these, and it would “dim” down to about the halfway point (it was actually really annoying flicker) and then just shut off after that, wasting most of the slider.
This is exactly why I have a dimmer in our bathroom, bedrooms and kitchen. When I had my daughter the last thing I needed was to have blinding lights wake us both up fully in the middle of the night. This way I could have just enough light to do what needed to be done, and we both just drifted back off to sleep. It made a HUGE difference in the quality/quantity of my sleep in those early days. Even now I will use the dimmers when I’m getting ready for bed as the low light seems to help my brain get shut down and ready for sleep better than bright lights everywhere.
I installed these dimmers, specifically the slider with the switch at the bottom, throughout my house. They work great. These work with (in my experience) CFLs and LED lights, while other dimmers in my house (more expensive) do not.
And we get the dress plates, where…?