I just pegged over 200k on my 98ML 320 and it's using 1Qt every 1,000-1,500 miles. I've just become accustomed to adding a qt every time my light goes on.
No Leaks, and no burning. It's been like this the last three years...since about 120k.

My 2000 ML320 uses no oil in 10,000 mile oil changes. It never has used any oil. However, only approx 50,000 miles on it. (Mobil 0W-40)

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Paul 1987 300 SDL; 2000 ML; '69 MGB; '68 VW Fastback

I've got 250,000 miles on my '99 Ml-320 and it is getting towards using a quart of mineral oil (always Castrol 10-40) every 5,000 mile change (inc/ filter). Bit of smoke in the air after I fuss around launching the boat.
This thread has reassured me that it is unlikely that a sudden increase in oil usage is in my immediate future.
By the way, replacing the oil pressure test port (like $20) cured an oil drip problem many miles ago. Some may mistake this for usage.