In my case they printed out 0.1mm smaller and the leads appeared to be 0.1mm bigger than intended, so the holders don't fit well and tend to drop out when handling, so for the ones I printed I used some glue stick to help them stay in place. But I'll definitely print more, just will make sure to scale them up a bit so they'll fit snug. Will do just fine considering that hygrometers are a tight fit inside these, at least for me.
I also have a suggestion for an improvement/remix: make a slot inside the holder so that the hygrometer sits more flush with the surface of the holder. This way you can make a bigger total contact area or a deeper fit inside the lead.