Im only familar with the Rocky Mountineer train. Never heard of the VIA one. The RM train is for ballers for sure. Average trip is like $3,000+. The RM train is amazing from the pictures ive seen.
A friend of mine travels by train all the time (scared of flying), and he quite enjoys it, but based on the pictures he sent me the sleeping quarters can feel kinda cramped depending on which bunk setup you get. Some of them get their own washrooms which is nice as they include a shower. Other lower cost ones are shared washrooms at the end of the car.
Koenigsegg, what started as a dream just blew your doors off.