A good small hotel in the "Beverly Hills" district of Denver. There is great shopping, galleries and restaurants within walking distance. The hotel is very plain from the outside, giving no hint of the luxury within.
Parking is expensive at $22/night for valet service, and there is no self-parking. The minibar is pricey; for instance $12 for a small jar of jelly beans. There is a Whole Foods grocery store one block away if you need a snack.
There is an on site concierge that can provide recommendations for activities and restaurants, but he seemed a bit frazzled. He made recommendations for restaurants but was resistant to making actual reservations until forcefully requested. The hotel has a gratis limo and driver that will take you and pick you up within 10 miles of the hotel; a very nice touch.
The buffet breakfast at $15 is good quality, and a great buy. Call Marriott for the "Stay for Breakfast" offer if available; this rate including breakfast for two was only $20 above the best Internet rate I could find for the same room, making the buffet $10/person. Breakfast service is friendly but was not very professional. For instance, the cook got the eggs order incorrect from the waitor, but she brought it over anyway and asked if it would be okay.
Rooms seem a bit on the narrow side for a luxury hotel but are impeccably clean, with very large televisions. Rooms on floor 5 and above will have a view of the Rockies if facing the mountains. Bathrooms are large and use a lot of marble, with separate shower and bath. Everything was in good working order. Public areas including hallways are clean and well maintained. We had asked for extra towels and they were always correctly replenished.
The checkout bill slipped under my door was incorrect, but was promptly revised upon notification. The front desk, bellhops and valets are friendly and professional.
In summary, a good hotel choice if you are in Denver in a fun location and I would stay here again, but lacking the extra polish you would normally expect from JW Marriott's top-of-the-line properties.