A while ago, I had several fans in my house and used the 14314 from Jasco/Enbrighten to control my fans over Z-Wave, with speed controls. They were awful, constantly breaking.
I moved to the Leviton ZW4SF, which looks like it's maybe being phased out? A bit difficult to find. They were always good to me, though!
Do you adjust your fan speeds with automation? What do you use? I am eyeballing either more ZW4SFs or the Innovelli, but the Innovelli is, as usual, pretty pricey.