West LA/Santa Monica, CA has two taxi companies that use old MB diesels, mostly W126's but some 123's as well (mainly TDs). They're called Taxi!Taxi! and Excalibur. Much classier than the usual ratty Crown Vics, and the engines last a lot longer between rebuilds (though the Ford 4.6 V8s are doing 300k+, so maybe not that big a difference).