They really impressed me. I’d used them before with lighter 52g catweewee springs, and I kind of hated them - but with the 65g Halo Clear springs (and some lube) they felt great. Moderate tactility, snappy operation, very quiet, and overall quite satisfying to use.
I call them “unholy” with the idea that the “unholy” in Unholy Panda derives from the donor switch’s name, Halo - like you might find above (or conspicuously absent from) an angel’s head. Unholy Pandas are Halo housings with Panda stems, and Holy Pandas are Panda housings with Halo stems - I tend to use “unholy” for any frankenswitch that utilizes a Halo housing, and “holy” for most switches that contain a Halo stem.