We first stayed in Bankai Orchid over New Year 2007/08 and thought it was absolutely wonderful so booked it again as part of 6 months travelling around Asia.
We were here in May and we knew it was going to be much quieter but for most of the time we were there we were the only people staying in the resort - this was fantastic for us as it was like having our own private resort but I think it's only because of the prices they charge - even in May we were being charged about 4,000 baht a night. They had made some nice upgrades to the bungalows since our previous visit but I don't think the rooms justify the price tag.
Breakfast is included, which depending on who is cooking it varies massively in quality. Other meals from the restaurant are generally good and reasonably priced.
You're only 10 minutes away from Haad Rin but it feels like another world as it's so peaceful and chilled and makes a nice contrast.
The resort is lovely but I'm sure you could find similar quality for a lower price elsewhere on Koh Phangan.