I have stayed for a week in this hotel during a business trip. The location was perfect for me, since our offices are a walking distance away from the hotel. For tourists or visitors of downtown Bonn it might me a little far from the city. Though it is close to a U-Bahn (subway) station and you can reach downtown within 15 or 20 minutes.
The hotel itself is very simple and business oriented. It's actually a conference center with rooms for guests. I stayed in a single room and had a single bed and my own bathroom. It is really small and contains only the basics (TV, wi-fi, a couple of cloth hangers and hairdryer). It's important to stress that there is no air conditioning (it has heating, I guess, but I was there in summer) or minibar (you can't store your own food/drinks). I you'd like to iron your clothes, you can borrow from the reception for free.
As everyone has already mentioned, the breakfast ist really nice and with lots of options, including for vegetarians. But the restaurant has no great options for lunch or dinner and sadly there are almost no dining options within a walking distance (you must also walk for quite a while to find a supermarket. For urgencies there is a gas station with a 24h store where you can find some snacks).
They also offer bicycles for rental for a € 8,00/day fee. It's not quite cheap, but it's worth it if you plan to ride beside the Rhein River. The hotel is really close to the river and the very nice Rhein Park