We stayed at the Bishop's House Hotel for 3 nights just before Christmas 2012. The hotel is in a fantastic location, right in the shadow of the Charles Bridge. This meant you were within 10-15 minutes of the Old Town Square or the castle! Being students we didn't particularly want to have to keep paying for transportation.
The room was absolutely fine, reasonable space, safe, tv, tea and coffee. However our 'double' bed was two single mattresses pushed together. But during a short city break in Prague I doubt many people will spend much time in their room. The bathroom, however, was fantastic. It was large and the shower was great.
Many people complain about the lack of choice at breakfast but I disagree. Considering the size of the hotel there was a considerable selection of cereals, breads, pastries. The cooked breakfast changed daily the 3 mornings that we were there.
All in all a good, solid hotel with a brilliant location. Would definitely return.