We were meant to stay in Glenbruar House but got upgraded to the main hotel, which was pretty flawless honestly. Super nice staff, everything was clean and worked well, perfect for a nights stay.
I got the impression that we were 'upgraded' because there were not enough bookings to require both the main Hotel and Glenbruar house, so it was just going to be easier on the staff if they just had all their guests in the one building, but honestly it was more convenient staying in the main hotel so not a problem at all.