It took practice and patience on my part, but I use one on my guys. It's got a little round head on it and I bought extra heads so they each had their own. Once they got used to it, I found it to be so much easier than fighting manually scrubbing with a regular 'ol toothbrush. Now I just hold their beards, move the toothbrush across their teeth and let the little spinning head do the work. And of course they always get a greenie after.
Bribery works VERY well with my furkids. hahaha They now know that if they eat that pill or tolerate that brushing that they immediately get a goodie for it.