I have a pair of those too & they work well enough.
My biggest problem is I'm missing one of the usual canine teeth you'd put these on. Visually you can't see the difference & this is the only thing that's ever been an "issue" with it & in the grand scheme of things it's not a big deal at all. I have to use them on the ones right next to my front teeth so talking, drinking, just closing my mouth is difficult with these but for different reasons.
If I ever want properly fitting fangs I'll have to see my dentist & that's just not worth it for me.