The old Renaissance on Quebec used to be the default 1K hotel back in the day of Stapleton. It was pretty good 10 yrs ago. UA just put me in The DoubleTree on Quebec the other day. Pretty good. If there is wx, you would want to be closer, but if the forecast is good, I don't think the 20 min ride is a problem.
One good note on The DoubleTree. Their 0900 shuttle was full, leaving only me. They whistled up a taxi and prepaid the fare to ensure I had no problems. Pretty nice customer service....