This is based on my experience there during Winterlious. I would say never go her during Winterlicious. They over booked reservations so decided to completely disregard them.
I called few days before to make a reservation and was told they were really booked up got a 7pm reservation.
Arrived at 6:50pm to the Brownstone and there was lineup of at least 20 people. The weird thing was no one ever asked you to confirm you name, or reservation time. They were basically taking people on a first come first serve bases. Which was very aggravating especially since people were cutting in line. Which if they had your name on a list or given you a number as you came in then it would at least have been fair. I had asked most of the people around me and most also stated they had a 7pm reservation. The girl directly behind me had a 7:30pm reservation. She was behind me though so that was fine since she never tried to cut in line.
It just stupid to take reservation and then not have them honoured. Don't take reservation just say it will be first come first serve but then at least have a list as people enter. It took about 40 minute wait before being seated. They Never offered an estimated time to be seated or an apology for the wait.
The food was very good. I had WARM GOAT CHEESE APPETIZER, NEW YORK STRIP LOIN & CHOCOLATE MOUSSE. The appetizer was very delicious. I had wanted CRÈME BRÛLÉE for dessert but they had run out when it when were ready for dessert. The mouse was good tasty though.
The atmosphere was nice, the food really good. Also considering price paid $25 for everything it was well worth it. If it had not been for the complete disregard for reservations and the long line of people waiting they would have probably received 4 stars.