I'm not going to say they are all the same, but many of the pricier ones are the same ones being sold on ebay for much less from vendors like aquatic magic. Same goes for some of the LED lights, etc. They are just re-branded. I've had a Rhinox for over 5 years and still producing that fine mist.
I believe I have the same fixed output regulator as you right? the Azoo one?
Which co2 regulator are you using the rhinox on?