While the EA, E1 and E2 were each built for a specific railroad and train, they were largely identical mechanically and were a step further away from the concept of custom-built motive power, integrated into a particular streamliner; and towards mass-produced standardized locomotives.

The E2's profile was more aggressive than the sloping snouts of previous EMC passenger power, so they gained a "bulldog nose" nickname.

One of the nicknames that these locomotives acquired, because of these portholes and prominent nose, was "Queen Mary," after the British Cunard liner had recently been put in service.

The Union Pacific Railroad also referred to the schedule of the "City of San Francisco," a passenger train hauled by these locomotives, as sailings.

The units were painted in Union Pacific's Armour Yellow with Leaf Brown roofs and undersides, the same colors as UP's previous streamliners (the M-10000 etc.).

The "A" unit of the LA set, LA-1, went to the Chicago and North Western (#5003A) and was scrapped in 1953 after it was destroyed in a head-on collision near Rhinelander, Wisconsin.

However the pair of Winton Model 201A V12 diesel engines from SF-1 (the lead unit of the City of San Francisco set, nicknamed "Queen Mary") were rescued from scrap and eventually became part of the collection of artifacts at the California State Railroad Museum at Sacramento.