If you can, go for the RC models. If not, make sure you get the gate valve mod for your RS. Euro-Reef are good skimmers. Not the best. But unlike Deltec and Bubble King, they are definitely worth the cost. They are built better too.
I used an RS on my 180. Great skimmer. Jon (scarface) will be prying it out of my cold, dead hands today.
With your sump and all those fuges, I don't think the RS 80 will be big enough for you.
fine tune adjustments to get the best possible performance. Much cleaner, less splashing and less noise than the telescoping drain. Put a filter sock on it and you'll never see micro bubbles from the skimmer again.