Ramada Don't
I stayed at the Ramada Inn Downtown Denver for a conference at the convention center. This hotel is approximately 1.6+ miles form the convention center (about $7-8 for a taxi ride). We had problems from the first moment when we tried to confirm our reservation and request a credit authorization to use the company credit card. 
Cons 
-The free shuttle runs only at the top of the hours and is always full. Expect to have to pay for a taxi. I don't know what the return is like because the van was always full then too.
-The ceiling height on the 3rd floor is somewhere between six and a half feet tall and not quite seven feet tall. If you are tall you might need to duck.
-Bathroom fixtures are moldy and dirty. 
-Entire hotel is outdated. 
-Furniture is old, stained, or worn. 
-Towels are threadbare. 
- Lighting is terrible and it is difficult to read even with all the lights on in the room.
Pros
-The bed is comfortable and the sheets are clean.
I would not return. Nor would I ever book this hotel for myself. Pay the extra money to stay closer and more comfortably to the convention center.