I purchased two extra large beds for my Lab and my medium size mixed breed who have hip and knee problems. The Lab had nothing to do with the bed for several days, but the mixed breed jumped right in and loved it. While my Lab was trying to decide if she would try it, my Chihuahua took over - what a sight - a little dog in the extra large bed. My Lab must be unusually long, because the extra large bed is too short for her, but she compensates with the bolster around the sides. Great bed.
Our exceptionally finicky cat has adopted this wonderful dog bed as her home -- it cradles her frail frame in comfort and looks perfect wherever we put it (was unsure about the color initially, but it is perfect given its neutrality).
I love the bed but it is not true to size. Measured outside bolster arm to outside bolster arm is 51" at best, not 56". I have to pull it taunt to get it to measure 51". That extra five inches means a lot to a 200 lb mastiff. I will decide by the morning whether I will keep it or not. Other than the size issue I love it.