I stayed two nights at the Vanderbilt Grace in November. It's a good looking property, and the location, though a bit hidden, is very convenient for restaurants, seaside and sightseeing. The public areas are elegant and homely, very inviting. There isn't a proper lobby, and the bar is actually part of the restaurant.
Our room was a junior suite, quite large and comfortable. The design was fresh and modern without compromising the sense of place you expect in a town like Newport. We were mistakenly given a deluxe room at first, and it was a bit small and basic, so I would advise any prospective guest to book the junior suite as the price difference is not that significant.
Service is a a bit informal and not the most professional I've enjoyed. There was a lot of talking between the staff and a bit of disorganization here and there, but all staff members were very friendly.
Breakfast in the conservatory was average, and the size of the room didn't allow that many guests, so there was a line on both mornings and some confusion around the buffet. Be sure to get there early. We didn't try the restaurant, but since the kitchen is led by Jonathan Cartwright, it's most probably just as good as the White Barn Inn in Maine.
There's a very nice indoor pool, and a well equipped gym.
I don't think I will be returning to Newport anytime soon, but I would definitely recommend the Vanderbilt as a very comfortable base from which to explore the area.