I received my HyLid order promptly and Matt was kind enough to swap one digital top for an analog so I could compare.
The lids are a clever idea, made of good quality materials and everything worked right out of the box. The extra batteries added for the digital models was a very welcome touch.
I have a bunch of hygrometers of different make and quality. I regularly use the "Salt Test" procedure to calibrate the best of the digital models then use it to check the others. My problem with all of them, Hylid included is the wide variation in RH readings. There typically is a range of +- 5% on both sides of my reference model (10% overall). This isn't a complaint about Hylid in particular, but the state of humidity measurement overall.
I'm well satisfied with my purchase and will consider Hylid again.