I've ridden the Zephyr multiple times - it really can be a wonderful experience, and you will see scenery that is only available by train. A few pro tips:

- For two people, the roomettes are more confortable than the bedrooms, IMHO. Regardless, get a private room, the privacy and relative silence are well worth it.

- Bring some snacks and cold beverages. Water, coffee, ice are gratis.

- Your sleeping car ticket covers all meals in the dining car. Take full advantage of this.

- These trains almost never run on time. I once rode the Zephyr Reno -> Denver and we arrived 15 hours late on a schedule 29 hour trip - literally the next day.

You can't be in a hurry nor on any kind of schedule. Look out the window and enjoy the ride. Utah in particular is stunning beyond belief.