Similar question from me - the car had a PPI from a BMW shop (but not one I'm intimately familiar with in terms of reputation) and they did not mention anything, but I just took the car to a dealership and they said it was the valve gaskets and $1200 to replace.
I had inspected this pretty closely when I bought the car, the driver side seems perfect but the very back bolt shown below is crusty, and some oil definitely dripped onto the header, but I can't say I've ever noticed a smell? (Maybe I just am still getting used to the new car smell and I think oil smells nice?)
The thing that I'm not clear of, if the gasket was the culprit, wouldn't a lot more oil be spraying out on the surrounding pipe? Would the bolt head be that likely to collect crap?
The finish on the valve covers themselves seems to be perfectly fine compared to some of the horror shows I've seen in other threads with everything bubbling off. Car only has 52k miles.
