I think oil burning under any circumstances is unacceptable. I would get that checked out under warrantee. I remember when my 190 started to burn 1qt/1000mi, it only deteriorated to 1qt/500mi. In the process the excess soot & raw oil clogged my pre-catalytic convertors. After new valve guides & seals haven't burned a drop for the last 170,000mi. Granted this might be a special case since the early 190's had notoriously poor valve seals. But I worked with an 95 Audi A6 2.8 whose healthy appetite for oil plugged both catalytic convertors with only 100k on the odometer.