I have a friend who knows a lot of furries, he dates furries, hangs out with them but isn't one. How he describes them, sounds awfully familiar to how therians identify with their animal spirit. According to him, the only real difference is that furries dress up like their 'animal' as well.
However, you tell a therian they're a furrie and many resent it completely. Furries seem to be seen on the same level as people who lie about sharing their soul with an animal however there is as much evidence of most of the furry population being therian as there is self-declared therians of being therian.