Review (3/5): Nit-Picks; Pretty Bad Quality, Seams Show....
I used this as a Undertale cosplay for Temmie (she's a white cat-like creature with grey hair). I clipped them onto some white earmuffs and they stayed on as expected; not very well. The problem was that the earmuffs were thick and it bended the clips on the ears so I had to use some rubberbands to keep them on, but this is probably not going to be a problem if you use them as intended. I did think the inside of the ears could look better as the fabric inside had a seam that stuck outward, but I wasn't too invested in the cosplay to care about the seam very much.
When put on hair they are quite flimsy and should need a few bobby pins to keep in place. Otherwise the product ended up being good enough...