We stayed at this hotel in end May 2011, and got a room with a slanting roof (on the 5th floor) so although the room was a good size, the roof made it slightly suffocating. The room was pretty comfortable, with very soft mattresses (too soft for our Indian tastes but Americans may like this). The bathroom was average sized but the shower cubicle reminded my husband and me of a cruiseliner shower-quite uncomfy.
As for the location, it is a hop-skip-and-jump from the Hauptbanhof but like all other big European cities, one finds sex shops and a "sex-video-cabin-show" in the area. We saw a few prostitutes and the area at night felt seedy but not especially unsafe. The paid parking is 2 minute walk from hotel and I would not really suugest an alone woman to use it and then walk to hotel.
There is a direct train (3 euros per person) to the airport from the Hauptbanhof. Quaint Koln is at a 20 minute distance by train. The luxury shopping street of Konigsallee is a 5 minute walk, and the Altstadt/Old town (shopping and pubs/restaurants) and the bars by the Rhine are about 10 minutes at most. They also give their guests public transport cards which make all public transport within Dusseldorf free. Trams leave from right outside the hotel.
My husband and I were extremely happy to have stayed here, and not the least because of the breakfast. It was simply one of the best we had on our trip. It had a widespread of cold and hot items along with all kinds of fancy coffees to 15 types of teas. One can order eggs sunny side up, omelettes, pancakes and waffles straight from the kitchen (yummy!)
The room was clean, and one day when we occupied the room right after the cleaning lady left, we had her supervisor knock to check if it was cleaned upto satisfaction.
"The Cloud" Wi-fi has to be paid for (5 euros for 30 mins, 10 euros for 120 minutes-can be used over 2/3 days) but remember to log out through "the cloud" website or else you'll find your minutes all over (like we did)! They had a computer and printer in the lobby but I'm not sure if that was free.
All in all, we enjoyed our stay here!

Clean, staff are pleasant but everything is dated and a little threadbare. No tea or coffee making facilities in the room, breakfast is not included and expensive at 23 EUR. On the plus side the room had a large flat screen with satelite tv and staff are very helpful.

Basically it charges too much and although it might have the specific items to warrant a star status, it doesn't feel like a 4star.

Stayed here for 1 night for business purposes. The hotel is located close to the railwaystation and walking distance (5-10 min) to the main shopping area of Dusseldorf. Check in did take quite long, even it was not busy. The room was very standard and for the price I expected more. The room was very clean though and the bathroom was nice. The hotel itself reminded me of 80's style decoration. Breakfast was OK, nothing special. Allthough I cannot say anything really negative about this hotel, I have stayed in way nice hotels in better locations.

Excellent location, right next to the main train station. Upon arrival, the hotel gives you a card that allows you to use unlimited public transportation. Had an encounter with a very rude staff member, but over all, it was a great choice.