We did it at Christmas 2016 when sister and niece were over from US. 12 of us plus two tinies, worked very well. Only thing was, taking mountains of food and not forgetting anything essential, since not near any shops!
Dd2's lovely partner did it for a birthday of hers - about 10 of us, one baby, it was lovely.
Dd1's MiL also did it for a big birthday, very big house and garden walking dist. from beach in September. There were at least 12 of them inc. several children of different ages and it worked v well. We were there but in our own accomm. nearby.
One thing, if it's at all a high season time of year, do book early! We left it quite late to book that Christmas so I think we were lucky to find anything so nice - a big converted pub with a pool table and table football - both v popular! thrown in.