Bad system for paying-once paid with the credit card when check in(you said just for autorization) and once paid in cash when check out.And my money are not restored yet in my card(already 8 days)

for summer, air conditioning in the rooms and not only in the lobby is necessary for a four-star hotel

I did not realise that the room had NO air conditioning. I could not sleep at night since it was so hot! I would recommend hotel to a friend in winter but NOT in summer. I would tell him to goto a room with AC.

Tolles Service, das Rezeptionspersonal hat sich durch besondere Freundlichkeit ausgezeichnet. Haben uns sehr willkommen und wohl gefühlt. Danke!

Klimaanlage hat gefehlt bzw. ist die Erläuterung dazu in den AGB bei Buchung irreführend -- ich habe (nicht zuletzt aufgrund der AGB) eine Klimaanlage im Zimmer erwartet

The hotel was well located with easy access to the subway, and we received an unexpected upgrade to a suite, which was also fantastic. The front desk staff were helpful and friendly. The breakfast staff, in stark contrast, were simply awful. The first day we arrived early, and though I speak nearly fluent German I apparently misunderstood the front desk person who said we could go to the breakfast room and have coffee only while waiting for our room to be ready. I thought she said we could have breakfast. The staff member in the breakfast room went immediately to tell the front desk we were eating breakfast and weren't on his list. I realized I must have misunderstood and offered to pay for breakfast. On one day of our stay our room was not cleaned. On the last day we checked out because we had an early train. My traveling companion went to the breakfast room to get a croissant, and the plate was snatched out of his hand, and he was told he wasn't allowed to eat because we had checked out.

Wegen eines Computerproblems kam es zu einer Überbuchung des Hotels. Kurzfristig vor Abflug wurde mir mitgeteilt, dass ich im Hotel Fürst Metternich untergebracht bin. Da ich mit zwei weiteren Gästen im Austrotel verabredet war und wir unser Abendarrangement in der Nähe des Viennart gelegt hatten, war es ehr ärgerlich nicht im gleichen Hotel zu sein.