We've wandered a long way from the original title of this post. But while we're on the subject of sleepercoaches, don't foget the "budget room coaches" operated by SCL in the late 1960s. These were 16 duplex roomette/4 bedroom cars originally built for B&O -- the only ones I know of in this configuration. SCL leased, then bought, the cars. They were named for birds ("Wren", "Bob-o-Link"). As "budget room coaches", they were quite a bargain, since the duplex roomettes were essentially the same as full roomettes.
(Interpreting this as a comment on 16-4 sleepers ...)
16 Duplex Roomette-4 Double Bedroom Sleepers could also be found on the GREAT NORTHERN (and CB&Q) and the MILWAUKEE ROAD.
The GN cars came in 2 varieties ... a 1947 variety and a 1950 variety, both named in the GLACIER series. Both were P-S products, and had center-bedrooms; the 1947 variety was of the "hybrid" type, with open hoppers in the bedrooms, while the 1950 variety had enclosed annexes. Most of these were scrapped, although several made it into work train service. I don't think that any were ever assigned to the EMPIRE BUILDER; usually found on the WESTERN STAR and other GN sleeper services. I believe that, when these cars operated in the WESTERN STAR in the "just before AMTRAK" days, the fare was similar to that of the competing slumbercoach on the NP MAINSTEETER. None made it to AMTRAK.
The MILWAUKEE ROAD sleepers were unique in that the bedrooms were NOT located in the center of the car! The 16 duplex roomettes were all located together, followed by the bedrooms, similar to a 10-6 of the time. These were a P-S product of 1949. These usually operated on the PIONEER LIMITED, although other assignments were always possible. All (4) were scrapped in 1969. So, obviously, none made it to AMTRAK
C&NW operated a similar style car - 16 Duplex Roomettes, 3 Double Bedrooms, 1 Compartment. (Another "hybrid" style ... bedrooms with open hoppers, the compartment with an enclosed annex.) None of these survive, to my knowledge.
P.S. to Mr. Norman ... seems that we could use something like a passenger equipment forum. Thoughts???