I was reading this thread and I never knew rabbits purred/grinded their teeth like that out of happiness! that is great!
I have a question, is it just a noise of grinding teeth? or when you pet their head can you feel the vibration? I was picking out a new bunny for myself and my family and I felt a vibration on this lionhead (ironically) head i was petting.
It depends on the bun, like you say, a Lionhead, a smaller bun, smaller head. So, yes, you would feel that before you'd feel it on a bigger bun. I had a minirex who grinded when I would pet her, or talk to her for that matter
, but yeah, you can feel it on their head if it's a smaller bun, depending on the agression of the grinding. If it's just barely, you most likely won't be able to feel it through the fur.
You might be able to feel it through the grinding though, if you are used to the movements of the jaw
.