I have stayed at the Radisson Blu Hotel twice now. The first time, I stayed in a Standard room which had a sloping roof which made the room seem very small. More recently I stayed in a Deluxe room, which had high ceilings, a beautiful rounded window and a king size bed.
The hotel is well-situated: about a 15 minute walk from Centraal (the main train station) but in an area close to the canals and full of character. You can easily walk to most tourist destinations within Amsterdam. The check-in process is efficient and the facilities are good. The rooms are equipped with decent toiletries, a hair dryer (which is very slow but works), an in-room safe, and the other standard features.
My husband and I return to this hotel time and time again because of its location and because of the consistent standards. I would recommend this hotel.