This is a timely topic. My 540i sucks oil from the PCV system it seems. It's ridiculous in my opinion. I really want to stop this was occurring. It's so bad, that oil is dripping out of my filter down onto the ground in front of the front tire. My Vortech pulls air from below and behind the passenger headlight. I hate it. Everything inside the intake tract is coated in oil. Is this the same thing you guys are fighting? My crank case vent comes in after the MAF and right before the blower.
I don't mind and fully expect some oil to coat the intake tract, but dripping out of my air filter is crap. Almost makes me want to LS swap the BMW