I'm in the same boat but with a 06 530i N52.
Same issues as well. Does your RPM play get worse when you turn on the AC? Do you have to add a quart of oil every 800 miles with no sign of leak?
Those are pretty much my symptoms. The PCV was cracked and I changed that, but I shouldve done everything at one time.
Any on this job and has it fix your problem?