Had 2 LGB Stainz Circus trains, one came with passenger cars, the other open flat cars. Used to run these to death.
Also bought the LGB Circus Sound Box car which was really cool, but the sound unit died in it, and never could get it to work again.
So I gutted the sound card and an '97 PSS Sound board was put in it, so I could just change out the other spare sound chips I have and use it for any train or loco type.
I have sound chips for: GP7/9, GP38-2, NW-2, or a few Steam assortment sounds as well as the rail sounds "clickety-clack, brake/wheel squeaks", so depending on whether the loco has sound in it, or if it requires an add-on sound car with the matching loco sounds, I can usually cover most of them for what I currently run.
Have a couple of cars the old 'PSS "pull and replace the 2 sound chips" on the sound boards these are mounted in, so I could have either American, European or Sound Effects in use along with the loco sound car if needed.
As for running, I ran those LGB Stainz's to their death. literally!
And they were my favorite, now since their demise, I'm running an GP38-2 Rio Grande and American freight rolling stock or Christmas Passenger cars {Christmas train}, need to get a Christmas loco, have two Christmas Loco's but both are in need of finding a way to add couplers to them as their coupler mountings have broken completely off {they look like NW-2's but only have 1 smoke stack instead of 2}, so got to rebuild something on them to be able to couple them to the Christmas Passenger cars, of which the baggage car has an real old PH Hobbies Christmas Music sound card that plays 16 Christmas Carols.
Trying to find a very small FM radio that will power a standard 8-ohm speaker, then try to power it from track voltage through a voltage reduction circuit and use my FM transmitter to send music through the baggage and other powered{lighted} passenger cars and possibly even the loco{es} via a 2nd mounted speaker, if room is available.
I also run standard American Passenger Cars {Bachmann}, just depends on my mood and time of year as to which train and type gets precedence on the rails.