I ordered a Large for my 12 year old retired PD. It seems very good quality, and certainly has a thick layer of foam for him to lie on & good bolsters around the sides. Looks like it’s going to last…time will tell.
It is somewhat larger than I’d envisaged, but that’s down to my buffoonery with the tape measure. He’s a lab/cocker cross & tbh a Medium would probably have sufficed.
Anyway, so far, so good. 👍🏻