My dog now sleeps better than the rest of the family.
As always, Zooplus delivered really quickly and I can't fault them.
In hindsight, perhaps I should have got the tape measure out, as I think the medium size would have sufficed instead of the large, but my dog loves the extra room to stretch out if he wants. In fact, the whole family can join him!
It looks like the sheepskin cover comes off the bed to be washed independently of the rest of it, which is a bonus as older dogs tend to leave more little marks around...all in all, I'm very pleased.