As far as I am aware of, the factory configuration has only one PCV valve and that is in the passenger side valve cover. This closes under boost. The pre-turbo to the drivers side valve cover does not have one. It is my understanding that under factory configuration this is primarily a fresh air source and a way to relieve positive crank case pressure under boost with the PCV valve closed off. Thats as far as the factory configuration goes. With the RX configuration, the drivers side valve cover PCV barb is capped off. The Passenger side valve cover goes to the inlet of the can. The two outlets go to the intake manifold with a check valve that flows only to the intake manifold, and to the pre-turbo inlet tubes with a check valve before the T fitting to both tubes. This check valve also only flowing to the tubes. Now, under vacuum conditions both suction sources (intake manifold and pre-turbo tubes) are pulling the air through the can. Under boost, the intake manifold connection's check valve closes, and still the pre-turbo tubes are pulling air through the can. Now if the intake manifold suction is greater than the pre-turbo suction, the pre-turbo line check valve closes so that you are still pulling the air out of the engine and not just by passing from the pre-tubo inlet to the intake manifold inlet. Hence the reason for a dual check valve configuration.
As far as my fresh air intake source, I just replace my air filter at each oil change and ive only ever seen just a couple drips of oil on the filter element, so for me its not an issue at this time. If it ends up getting bad, Ill do the same and get a clean-side separator. My catch can is the Mishimoto Baffled model. It seems to be doing well. All my return lines from the can to the engine have been clean with no residue, so I guess its filtering the air just fine. I did put a layer of SS Steel Wool in the can to give the can more surface area to condensate on. Thats about it though. I think the biggest thing that helps catch cans is being mounted up front and staying cooler than engine temperature. This gives them greater ability to let the dirty air condensate and drop the oily mix out of the air. I am by no means an expert on this, this is just my understanding of the PCV system on the ecoboosts.