My mini dacshund prefers to sleep in or under anything, so I thought this would be a perfect bed.  The instant I took it out of the box and put it on the floor, he climbed in, sniffed around went to the very back and layed down.  I bought the small size since he only weights 12 pounds, but I  had to remove some of the stuffing so it would not 'swallow' him up. After that it was perfect and he loves it. The stabilizing wire that holds the 'ceiling' up is perfect to keep it open. I really like the fact that you can remove the pillow that holds all the stuffing completely without a mess before washing the bed itself.  I highly recommend it.