I just returned for a three night stay at this property. As a Gold I was given comp lounge access and a nice room on the Club Level (7th floor of the hotel building). As other have pointed out, the Imperial Lounge is a separate building accross the driveway from the main hotel. The breakfast buffett was fantastic and the spread of snacks, coffees and drinks was very plentiful throughout the day. This is a nice hotel and I would recommend a stay here to anyone. I've also stayed at the Vienna Marriott right on the Ring and like that property as well - it has a better location for the city center.

And by all means, to get to/from this property from the airport take the S-Bahn instead of the CAT. I've done both on trips to VIE. The CAT is great if you are going to most places in Vienna. However, for this hotel, the S8 line goes from the VIE Airport station direct to the RENNWEG stop in far less time than the CAT+transfer option. It's also much less expensive.

Also noted, the Tram 71 from the top of the hill will take you right to the Ring in about 5 minutes. From there, you can hop the 1,2 or D trams to get around the Ring and to other destinations.