We initially wanted to stay here for three nights but decided to try for one night and if we really liked it, maybe book the rest there. We requested a air conditioned room that was non-smoking. We got a smoking air-conditioned room. Upon return to the front desk the agent just kept saying we have NO rooms that have air conditioned and we kept saying we're in one, can we just get a non-smoking one. He seemed agitated and asked didn't we ask for a smoking - my recollection no one asked us that upon check in. We were just so tired from the drive that we ended up staying in the room.
Upon check in, no one welcomed us, invited us for breakfast or provided any information. We had to ask for it all: parking, internet access, breakfast.
Overall the hotel is beautiful and unique. Would I ever go back again, definitely not. Not with such sub-par service. We're staying at the Westin in Frankfurt now. They're definitely a four star hotel with a five star customer service rating.

We stayed in this hotel for a night with colleagues. We wanted to save a bit of money on the rate during the Messe, but if you add the taxi fare [32 Euro] to the price of the room, you are better off staying at any 3-4 star hotel in Frankfurt.
The rooms are in a different, dorm like building, separate from the reception building. The rooms are very basic, small but clean. The only thing I disliked was that I could hear the water running from the surrounding rooms, when someone was taking a shower.
I'd only recommend it, if you have business nearby. As it is too far from Frankfurt by a taxi.

The food didn't taste of anything, and in the middle of dinner, the fire-alarm started, and didn't stop for about 30 minuttes.
Strangely, noone reacted to the fire-alarm, and no information was passed out to the guests.
Also we had to wait forever to order and pay.

Hotel rooms were small and they were not full at all, but we were given a room far away at the back. Breatfast was E 15 each day - very expensive and food was not covered and small flies were hovering all over: when this was pointed out, restaurant manager just covered it instead of removing it all together.

We found the service terrible: the hotel staff did not have any information about tours or tour times: we were told no tours were available on holidays and we found out that was not true. Staff also told us to use the outside path to get to our rooms with our bags on a cold and rainy day: there was an indoor path which they did not mention at all!! Staff was couteous but just had no clue about their own services and did not seem to notice or care what guests needed.

House keeping was also not very good at cleaning our rooms: garbage bins were not cleared and our beds were not made most mornings. This was an old abbatoir (slaughter house) and frankly, we found the atmosphere very strange - rooms and main building are separated and spread out: very inconvenient for the elderly. We booked this hotel through United Airlines.