We sailed from Nuremberg to Budapest 12 - 19 July 2014, and thoroughly enjoyed the whole trip. The crew was exceptionally friendly, upbeat, and helpful, and the food was great, plentiful, and varied; the evening activities were fun. Ship is clean as a hospital. Ship holds about 188 people, so by the end of the week you get to know most all of them, at least by sight.
There are no exercise / fitness facilities on the ship.
Arrival and departure went without a hitch.
Lower cabins are fine - experienced no noise or other inconveniences. Keep in mind there are only high portholes on the lower deck, so viewing is not really possible. (But you didn't come on this trip to spend time in your cabin now, did you??)