We just returned from staying a few nights at the Millbrook Inn. We stayed in the Octagon House, however, and can't comment on the quality of the Inn itself or the food there.
That said, our stay was very pleasant. The Octagon House is very much like a cottage, so don't expect fancy amenities. However, it has all that you need for a lengthy stay. We were very comfortable with five people. The house is equipped with a working kitchen, various pots and pans and some basic sundries. As a result, it is not hard to cook and eat there. One bedroom has an ensuite, which is very convenient.
The photos on the web do not depict the actual size of the place, which is larger. There is free cable, a DVD player, and free local calls. The gas fireplace is lovely to sit around. There is a basement area with plenty of storage, especially for ski equipment. There is also a washer and dryer, which is very convenient.
The property itself is gorgeous, with lovely views of the Inn and the valley. If you are a skier, location is perfect: just miles from both Mad River Glen and Sugarbush. There are many shops and restaurants a short drive away in Waitsfield, which is a very pretty town. Nearby are several other equally gorgeous towns, and of course the contryside is beautiful.
A word of warning: Vermont in winter is not very forgiving, so be sure to travel in a vehicle that can handle slippery conditions. On two occasions we had trouble getting up to the parking spot for the House.
Overall we were happy with our stay and would not hesitate to recommend the Octagon House at the Millbrook Inn.
