Hotel is not bad, however not too modern. Also if you have a room facing the front side, it can be noisy due to the traffic on a neighboring street.
Breakfast was more than ok, and the bathroom was clean (however not modern).
Staff was also friendly.
However I paid 80 euro per night which is - to my opinion - too much for this hotel.

We stayed for a week at this comfortable hotel - very clean, great breakfast included, helpful and friendly staff and excellent location. The beds and bedding were very comfortable, and the spacious modern bathroom was spotless. We highly recommend this property and felt the value can't be beat.

We selected the Hotel Am Bismarck for a two day visit in August 2011 on the basis of Trip Advisor reviews and were certainly not disappointed. The location is excellent - short walk to the station (great for day visits by train to Heidelberg, Ulm and Mainz) and easy walk into the city centre. The room was of good size, air conditioned, and with very new modern bathroom. Breakfast room was welcoming and offered a good selection, especially fresh fruit. Special mention of the staff, especially Renate, with her welcoming manner, and excellent restaurant and city walk recommendations. Although Mannheim is a train and transport hub, and not one of the usual tourist city visits, the hotel made it a wonderful introduction to our visit to Germany, and is strongly recommended.

Great location within 10 minute walk oif train station. Area was clean and safe. Nothing of concern even though we walked from train at 1AM on a Saturday night.
Hotel was clean. Room was rather large with very nice bathroom including large walkin shower.
The breakfast (included) offered a wide assortment including some items I had never seen on a german hotel buffet before. Items like peanut butter, roast beef, phillie cream cheese. They obviously get a lot of americans here.
We stayed here because of its proximity to the Bad Durkheim Wurstfest and the ease of travel between the two. We plan on coming back for the Christmas market and general sightseeing. Will definitely stay here.