Excellent Location
I stayed here in April while attending a convention at the Denver Convention Center. The Comfort Inn was one of the few hotels offering government rates for convention attendees so I tried it.
It was an easy walk from Comfort Inn Downtown (CID) to the DCC and to many restaurants and bars in the neighborhood. But the best thing about the location was that it was literally across the street from the historic Brown Palace Hotel, a Denver landmark. I enjoyed dinner at Brown's informal restaurant one night and had a drink and watched the NBA playoffs there on another evening. There is no lobby bar in the CID.
I agree with an earlier poster about the cramped breakfast space. Content-wise the breakfast was fine--eggs, potatoes, sausage for hot-breakfast types and fruit, yogurt, toast, and breads for lighter eaters. But they need to find a way to expand the dining area. This is a pretty large hotel and the space to sit to eat is miniscule. Add in people's luggage and possessions when they're checking out and you've got kind of a mess on your hands.
My room was fine, but not exceptional. The bathroom left something to be desired; it was tiny and awkwardly arranged. Specifically, the bathroom shelf where one might expect to put toiletries was too narrow and had been cut/angled to accommodate the toilet. It worked out because I was traveling alone, but I expect it would be more difficult for a couple.
Service was satisfactory to good. I got the impression that they needed more front desk staff. The staff who were there were very helpful but spread too thin. The front desk person very kindly locked away my bag for the day so I could check out and attend the last day of the convention.