We had a nice stay overall, staff was friendly and helpful. Location was terrific, close to u-bahn, restaurants and shops. Internet a bit on the slow side, but ok.
Only reason we would never choose to stay there again was the horrible noise from trucks unloading groceries to the supermakets across the street. Every morning between 6-9. You would expect some noise staying so close to a busy street, but this was something else! Unfotunately it ruined our stay at Mercure completely. If you are to stay here, make sure to get a room with no windows facing the street. Sad, because the hotel itself was perfectly fine!