Railfans have nicknames for everything, but the nickname “Amcan” for the Amfleet coaches is perhaps both a description of their barrel-like shape and that some complain that they are less spacious than alternative passenger equipment. Amfleet is derivative of the original Metroliner MU cars having the barrel shape and low ceiling – perhaps as a concession to aerodynamics, perhaps as a styling feature to make the cabin more airliner like as a marketing feature from a time when airline travel was considered exciting and glamorous. Adding to the confined feeling are the narrow windows, a concession to the cultural and social history of the U.S. where the throwing of rocks at trains had become commonplace.
One feature of Amfleet, however, is that they are ten and a half feet wide.
For whatever knocks people have on Talgo ride quality, whether it is the single axles, rough track near Seattle, or other factors, I have not heard much criticism about their lack of spaciousness. Talgo coaches, however, conform to a European Continent loading gauge and are only 9.65 feet wide on the outside. This also true of the new Talgo 8 being manufactured in Milwaukee – see http://www.talgoamerica.com/series8-passengerCars.aspx
England has an even narrower loading gauge, and I have read complaints about the cars they brought over into Canada and also about the seating arrangements in the Pendolino trains they have in England.
The United Aircraft Turbo Train, a very Talgo-like train from the early 1970’s, was 10’6" wide, and the extra width (over the 10’ 0" of lightweight streamline coaches) was one of their selling points. There is anecdotal evidence that in the mid 1990’s when the Midwest Regional Rail Initiative got underway as a plan, that Turbo Train inventor Alan Cripe was pitching a Turbo Train II – his Fastracker D