I owned the RO
BH2000 and it was very impressive. I can't comment of the aquamaxx since I never owned anything from their line of products.
For any HOB
skimmer you choose, keep in mind that the water level is very important when it comes to producing consistent and efficient skimmate. When I had my BH2000 on my display tank, I had to constantly keep an eye on the water line. Eventually I got tired of topping off manually and got an ATO for the display tank. All the equipment become an eyesore with so many things hanging on the tank (heater, lighting and PH chords).