Vertex and Reef Octopus Skimmer Questions

So I have narrowed it down to the Vertex IN-180 skimmer and one of the Reef Octopus skimmers from my sump. My first question is do I need to make a small stand in the water that either of the skimmers (once I choose one) can go on in the sump or if it is necessary or any benefits to doing that? My next question is what is the difference between these Reef Octopus Skimmers listed below?

Reef Octopus NWB-150
Reef Octopus DNWB-150
Reef Octopus Extreme Series EXT-160
Super Reef Octopus XP-2000

Now with that being said which one of those would I be better off for my sump? I found those all at salysupply.com if anyone needs reference. If I had to choose I was leaning more towards the Super Reef Octopus XP-2000 but if anyone can explain the difference between all those that would great cause I'm not a skimmer expert

 

Most in sump skimmers do have a recommend water height in the sump. I've heard good things about the XP-2000. Now I have had 2 Octopus skimmers DNW200 and DNWB-200 and they worked ok, but were rather loud. Might also look at the Bubble-Magus Skimmers at Nuocean - Bubble Magus I just installed the BM260 and couldn't be any happier.

 

Hopefully this link helps

http://www.3reef.com/forums/protein...eview-super-reef-octopus-xp-2000-a-75705.html