Thank you everyone for any guidance.
I think I'm confused about the difference between DCS and ProtoSound.
One of the things I like about DCS is the ability to run in scale MPH.
When I'm looking at locomotives at MTH web site, I look at the description for the words "with the digital command system"
I've been under the impression that this means the loco communicates with the DCS system, reports miles run, hours run, all that.
Some do not state this, for example the loco from 30-4142-1, it says passenger station proto effects.
So basically, do all 21st century loco's have these features (I mean except those that state they are conventional only)?
Thanks again