We stayed for 2 nights during December 2005, in a 'grand room with castle view'. Upon arrival at 5pm, our room was not ready. I don't know whether I have been unlucky, but, whenever I stay at Sheraton hotels, the rooms are never ready, regardless of the time of check-in!
Our room was on the third floor and overlooked the the front entrance of the hotel and Edinburgh Castle. Don't expect to get a full view of the castle, as the location of the hotel does not allow for this. The room was fairly large, and consisted of the usual dark wood furniture, it was clean and the bed large and comfortable. The bathroom let the room down, it was in need of a refit and was a little on the small side compared to the large bedroom area. There was a selection of sea kelp toiletries and complimentary bottled water in the bathroom.
The hotel has three restaurants, we ate in The Terrace on one of the nights. This restaurant is a buffet/carvery, where you help yourself to whatever you want for a set price.
We ate breakfast on both mornings in our room. Although the breakfasts are expensive, I have to compliment Sheraton on the service, range of food provided and the way it is presented. Breakfast comes wheeled in on its own trolley that opens up to a small round dining table. Whilst consuming cereal/fresh fruit, your cooked breakfast is being kept hot in the compartment in the trolley - nice touch. Recommended!
Didn't use the spa, so can't comment on that. The bar in the restaurant is nice and the staff are very friendly and helpful.
Overall, a nice hotel, good location as its only a short walk from Princes Street, the Royal Mile and the Castle. I don't know whether I would place it in the 5* category though.