I stayed here for 5 days last week. Hotel is amazing, building is charming. Very close to the Schönbrunn Palace (1 minute walk) and Heitzing Metro Station (1 minute walk).
It has been renovated and opened 2 weeks ago and fully booked. We stayed with corporate rates and it has very proper price to stay long. Rooms are new, beds and pillows are verrryy comfortable, hotel entrance and the bar are charming. I'll stay there in 2 weeks and it is highly recommended.
2 things;
1. there is no wifi at the rooms
2. Rooms are very far to the loby, dont forget anything in your room:))

Near the Heitzing Metro station and the Bus/Tram Station. One can go anywhere from here using Vienna's excellent public transport network. Rooms are very good. We stayed in a lower cost room, which was still very good. Only problem - no fan in the room. Property very good, great buffet breakfast. Recommended for anyone visiting Vienna. I travelled here in August 2008, but as there is no option for that in the date column, I am marking the least recent date amongst the list.

The fact is, it is a really old Vienna building, so because it's been let go so much, it really sets the perfect mood for a horror movie!
The basics on which the hotel is founded is perfect: Great location, built by the king for his guests (the hotel sits adjacent to Schonbrunn Palace and Gardens), so there is great elegance, opulence and ambience... but it needs to be fixed, pollished and made shiny again!
But, the sad thing was that while on our stay there, the rooms where just scary outdated and the carpets and wallpaper filthy.
Easy access to the rail network into the heart of the city. Nice cafe's nearby.
All in all, the saty was good - suppose because we were 3 couples that celebrated Sylvester Abend.. so the New Year's vibe made it better.
Good thing is that I did write a note to management and thanked them for VERY FRIENDLY hospitality, but that the hotel seriously needs attention. He did respond and I have been made aware they are now apparently renovating??

First of all, being a Romanian we got scammed by the company "Interra" from Romania. We overpaid for 4* hotel from 30th December to 2nd of December 1200EUR/room. I was so persuasive that I invited 2 more couples.

When we arrived we received very poor rooms in nearby building. The rooms were awful: fungus on the walls, the paper wall was missing in some parts, furniture of bed quality, and to be honest I felt like I travel in time (in a bed time).

After a long argument with the management we decided to leave the hotel, nevertheless they were persuasive and convinced us to stay on an upgraded room.
On the hotel restaurant I saw a rat (probably Ratatouille) :) - and this is not a joke.

The Viennese ball was really great.

The hotel is old and needs repariment. DO not go there!!!