Sorry for the long time with no updates...
I received the skimmer last week and my first impressions are that this skimmer is completely amazing. It produces the darkest, densest foam I have ever seen. The foam kind of breathes at the top of the column like it's alive.
It wasn't too hard to set up but I agree with some other posts. The directions are very lacking. All it comes with are some basic diagrams and that's it. If you already know some about skimmers then it shouldn't take too much to figure out. But if you barely know what a skimmer is then this could result in a real problem.
The pump already came with the mesh mod impeller and so I just left it in. They gave me some extra mesh and wire ties to rebuild it if I need to. They also gave me a regular needle wheel impeller if I decide to use it instead.
The pump is virtually silent. It makes my old Rio pump sound like a trashing machine. It pulls in A LOT of air. You can really feel the suction on the intake. The "muffler" that it comes with also works well. It almost completely silences the air flow.
I am using ozone with this skimmer and it already maintains a much higher orp than my old one. I still have the same 350mv setpoint but the swing is much wider. Where my old skimmer would drift the orp up to around 380mv before it started to fall, this skimmer causes it to drift up to 420mv... then the orp stays there much longer before it falls back down again. This makes my ozone unit work much less and yet maintain a higher orp in the tank. As a result the water is the clearest it has ever been.
One drawback though... The skimmate is so dark and nasty that you can sort of smell it from a distance. My old skimmer produced such watery skimmate that I never could smell it. This stuff STINKS! (but that's not really a bad thing). Now I just need to find out how to ventilate the room to get rid of the smell.