As an EMU,Metroliners became "shop queens",before and after rebuilding,however,as the shells were converted to
coaches/cabcars,they became a useful part of the fleet,2 cars found their way to be part of Amtrak's Biz car fleet
(9800,conference car,and 10005,Catenary inspection car)
Over time 2 Acela I sets will stick around,1set for high speed track geometry testing with the Acela track Geometry car,
the other set for Charter work along the NEC(Baseball/Football team charters,etc...).
Not sure if the "Eurostar" used in the "Chunnel" services between UK and rest of Europe has
started a 2nd generation design yet, could be adapted for NEC,"Eurostar" has to run
across many different Catenary voltages/hertz(AC+DC)and different Cab Signal systems.
At least on the NEC,2 different Catenary voltages and 1 hertz change,with ACSES/cab signals
across the entire corridor.
The Land of Enchantment is not Flyover country!