I had a bedroom on the Coast Starlight.. and when we walked through other cars to get to the dining car, we had a chance to peek in and see the roomettes.
They look cozy for one person.. two people might be a bit crowded for an overnight trip. Basically there's no additional space beyond the doorway. A convertible closet, I suppose.
If you're going by yourself, a roomette is sufficient.. if it's more than one person, I would go for the bedroom.
Another advantage of having a bedroom is the private toilet. Don't count on your fellow passengers to have ..um.. good toilet manners.
