Hi Jaquesdp08 - are you hard set on those brands of skimmers?
All, except for the AquaExcel and the ReefOcto ranges, are "break-the-bank" type deals.
Why not investigate the Bubble Magus range as well?
I know that I may sound like a "sales man or rep" for Bubble Magus. But, I did indeed find that I got a skimmer which performs excellently, for the price.
If cost is no option, I would say go for the Deltec AP902 skimmer or perhaps Bubble Master/King BM-250/300.
If you would rather get value for money, compare the ReefOctopus, AquaExcel and Bubble Magus skimmers.
The model I have, of the Bubble Magus range, is the BM-260. It is an external skimmer, which stands about 720mm high, and has a diameter of 220mm.
It is gravity fed, and has 2 x recirculating AquaBee 2000/l pin-wheel pumps, which together sucks 1400 litres of air per hour. The bubbles are extremely fine.
When I set my skimmer to run "dry"'ish, the skimmer produces 25 litres of very dark and extremely stinking skimmate in a week. And the neck of the skimmer then still get's silted up with crap.
When I run this skimmer in a medium wet mode, I get 25 litres of skimmate produces every 3 days.....