The RBR happens to be my least favorite. I've taken a video of its function cos I can't see for myself. It works as far as I can tell with the vortex and all. More water or less water don't seem to bother It, So I'm guessing its at least close enough to the real thing. Pure speculation on my part though.
Using it as it is, I feel it's pretty meh. Gets dirty fast. Using a dropdown, is not ideal either. Just cannot find a sweet spot with it. It doesn't suck. Just not as good as the others. I've kept it away. Slowly finding the ones I like best. Sucks cos i had high hopes lol.