Took this train last month. Be advised that our experience at Canadian customs in Vancouver was awful. The arrival area where you de-train in Vancouver is completely fenced in, almost caged, and narrow. A lot of people in a small area, with a very slow moving line. Customs agents with a sniffing dog walk among you. There is virtually no provision for luggage so that if you have more than a single overnight case, you are in trouble. You must wait in this large slow-moving line in the small fenced area nudging your luggage foot by foot. When you manage to get through this unpleasant experience, the next hurdle is obtaining a taxi by the station entrance. There was one cab waiting for a crowd of about 25 travelers that wanted taxis. And more did not arrive quickly.
Not to say that the train wasn't very nice. The Cascades to Vancouver is a very nice train. And, of course, Vancouver is a great tourist city. But the customs experience was very third-world.