Yes and doesnt the status of the bores even on visual inspection reveal condition of the rings? Meanwhile I've never heard of MB crank and bottom end bearings giving up easy.

Hell, if it was me I'd change the oil and deffinitely run a wet/dry compression test ASAP - even with the engine idling/operating under blown head gasket conditions. That oughta be the first and best diagnostic step anyhow to help figure out what the rings are doing at least. Also to help tell you exactly how blown that headgasket is. And how's your oil pressure?

I hate it when mechanics start selling astronomical repairs to finicky types (am not adressing anybody personally) treating these as "fragile" automobiles. Truth is the Stuttgart shortblock is tough as nails.