Hotel Klopp - CenterHotels: Avoid at any cost

On our way back from our wonderful Greenland trip, we had to spend a short (aka 5 hour) night in Reykjavik. I had booked the Hotel Klopp from CenterHotel in advance and it turned out to be the biggest disappointment in the entire trip.
The management is incompetent and irresponsible. We were expecting to arrive late at the hotel due to our flight schedule. I had informed over email that we would be late, but this wouldn't be a no show. We needed the room to sleep. even for just a couple of hours, before heading to our next flight. I had received a response that it would be no problem and the reception would be open 24/7. We arrived, with 2 sleepy kids and tired adults and the front desk person told us that there was no room for us! They had "upgraded" us to another hotel of their chain, and we had to take another taxi to get to the other hotel. This, in the middle of the night, during Gay Pride! It took us 20 minutes to even get a hold of a taxi, and by then we were so irritated. They had ripped us of 10% of the sleep we would be able to get that night, the kids were so unhappy, and the front-desk manager just kept saying there was nothing he could do. We ended up asking them to book us into a different hotel, where the location would be more convenient (since we had to find another room anyways). I am still trying to negotiate to get a partial refund for this awful customer service, but without success so far. Not a good track record.
I hope this blog article can be useful to anyone who is looking to book a hotel in Reykjavik. Please avoid Centerhotels in Reykjavik if you want to have a good stay.