And the dimmers must be rated for LED/CFL as well. I wouldn't count on "we don't use the dimming, we set it on high" - they might use a physical switch to bypass the dimming circuit on FULL ON, but I'm not sure, and some one might unintentionally turn them down. They likely just set the semiconductor to FULL ON, and if it isn't rated to handle the reactive load that an LED/CFL present, it could be bad for the dimmer and/or the LED/CFL.
And beyond that, my experience is that the interaction between a CFL/LED rated dimmer, and a dimmable LED is still fuzzy. As I described earlier, my rated dimmer/LED combo fluctuated in brightness randomly - just moved up and down, rather than hold a steady level (not a repetitive 'flicker'). I had to add a filament bulb to that group, and that seemed to damp out the reactance enough for everything to work. But then you can run into the filament and LED not dimming evenly together, but that seems OK to me.
-ERD50