I never had any trouble making a "Sea Clown" work for me. Nothing scientific, but when I kept my reef in the past, both it and my Red Sea Berlin pro classic produced similar amounts of skimmate (based on observation). I would certainly buy another one used if the price was right.
My current projects are growing my mandrake forest, and getting my tank to be a bit more naturally stable. I think I need to get about 20 more snails as well, the algae is starting to get a bit out of hand.