I flew in premium to Sanford from Nottingham, have also used Virgin's premium offering, here are my thoughts.
The seats are at the front of the plane. The entertainment was excellent, the seats were big and comfy and best of all the food was of a high standard, far better than Virgins. As another poster said, it also included the clubhouse at Sanford.
The downside? There are toilets at the front of the plane on either side, people from economy were constantly queuing in the premium area, at one point there was a woman standing in my wife's space in between her feet. My son is Autistic and he was getting a little stressed, the cabin crew did nothing, even when asked. I think even without a child with special needs it would have been annoying.
That is the only moan for me, the bottom line is for me I would use them again, but the price for their premium offering is way too high now. There is little to choose between them all in my opinion.