Jack500, I'm curious about this too, as I'm in about the same situation with a slight oil leak around the head gasket, similar consumption (I think), and 145K. I do notice that the only time I see blue smoke is on acceleration from rest after standing, and the longer I've been stationary at idle the more I see. The car is new to me this season, and I *think* that I see more consumption in big-city stop-and-go freeway work than I do in my normal mid-size city driving without major freeway tieups. My guess is valve guides rather than anything else, but would appreciate your own insight--and, of course, words from the gurus will be most welcome!
'97 SL500, 40th anniversary edition
'04 Olds Bravada (SWMBO's)
'06 Lexus ES330
'89 560SL (sold)
SL--Anything else is just a Mercedes.
(Kudos to whoever said it first)