So it looks like you fell for the OCC "scam" as well, didn't you
The facts about OCCs are as follow:
1. Not a single Oil Catch Can can capture 100% of all oil fumes without choking the PCV system. Yes, they help, but again, not one of them will give you 100% efficiency.
2. The Oil Catch Cans work ONLY during times when there is boost! That's how the PCV check valves change the flow of the air. During cruising AND deceleration, the fumes do not go through the OCC.
Also, there are two check valves that can go bad. One is integrated into the valve cover itself and one is in that little tube that goes to the back of the rear intake tract.
Rob@RB sells upgraded PCV check valves for the one that screws into the valve cover itself. Users are reporting good results with those.
Finally, I've noticed that once the BMW factory oil gets about 3000 miles on it, the car starts to smoke more and consume more oil. If you have a fresh change of oil there is no oil consumption/smoking.