This is the second one we've bought. We have 2 kitties and so we tried one Cave to see how the kitties would react. They both sleep on the 1st Cave, one kitty more than the other. Bought another Cave so both kitties will have opportunity to sleep on or in their own Cave. I expect the kitties might like the cave aspect of it more as winter gets here.
The construction is heartily made. The shape is flexible and does come back to its cave form with a little coaxing, even after a kitty has slept on it collapsed for weeks.