Today we received all four of our Mammoth Memory Foam Dog Beds we ordered to replace beds we bought 4 or 5 years ago. The former beds were great. I despaired over throwing them out but these new beds are even better! The thick memory foam will definitely help the older dogs with joint issues and our dog that has hip dysplasia. All four dogs LOVE these new beds and they took to them immediately! I love that you made available a nylon liner and extra covers! This will certainly make keeping all the beds clean a simple job. Thank you for manufacturing such a fantastic product!