It's a great skimmer. I've owned 2 of them over the years, and on the 20" cube I'm setting up, I'll be using a Deltec MC500 (the internal version). I'll be using it, because for that size tank, I don't think there is a better skimmer. I know how easy it is to fine tune, and what it's capable of. I've never seen a hang-on skimmer pull out nastier, stinkier skimmate (I have no experience with the new Octopus hang-ons with bubble blaster pumps or the ATB Hang-on cone, so I can't say whether it is better than those or not, but it's, hands-down, better than every other hang on skimmer on the market). As for price, $150 is a pretty good price depending on how old it is, but I used one for about 5 years and it worked just as good the day I sold as it did the day I bought it, and I bought it used. How big is the tank you plan on using it on?