I just got back in October from an award stay at the Hilton Zurich Airport. It was very close to the airport, and they have free shuttle service from the airport. I found the lobby to be a bit small and cramped, but it could be due to the construction. I was upgraded to the executive floor as a diamond. I actually had 3 rooms reserved for my family and we were all upgraded to the executive floor. I also had a comment in my reservation that I would be arriving at 9am in the morning, since my flight was scheduled to arrive into ZRH at 7:30am. Our flight was almost an hour early (hard to believe, I know)and we breezed through passport control, so we actually arrived at the Hilton at 8am. They were very apoligetic that our rooms were not ready, since they weren't expecting us till 9am. They let us sit and enjoy breakfast in the executive lounge, and our room was ready shortly there after. If you arriving in the early morning, definitly let them know in your reservation, so that they will be ready for you. I am not sure I would have made it that day in Zurich if I wasn't able to come in and catch a few hours of ZZZ's.
I didn't find this hotel to be super luxurious,