As said above, the roomette is "cozy." If you're travelling alone, the roomette is just fine, especially considering how much the larger rooms cost. I've travelled quite some distance in roomettes, always alone, and always been perfectly comfortable.

If you're with a companion, then the roomette might still be fine, but it will be "cozy." Remember, though, it's a train and you can always get up and walk around--or spend your time in the cafe car/observation car/whatever.