I've stayed at both the Marriott Grand and Royal hotels in Moscow. Both are very nice properties, excellant service and beautiful facilities. They are better than any standard Marriott hotel in the US - more on the scale of a JW Marriott.
Comparing between the two in terms of atmosphere, the Grand feels larger. It has a wide and open lobby area that makes the hotel seem busier and more active. A large and lavish breakfast buffet every day. The cafe is also opened for lunch and dinner with standard western food. Also available is a Russian restaurant and an upscale western dining outlet for dinners. Glass elevators offer nice lobby views on the way up to guest floors. The Royal feels smaller and more intimate. Darker wood tones in both the lobby and guest rooms. Less choice of food outlets. Guest rooms, though, feel more comfortable - softer beds and richer dark wood furnishings. I haven't eaten in the Royal so can't comment about the food though I'm sure it rates highly. Piano and harp players accompany diners during lunch and dinner. Sunday brunch, in both hotels draw a large local expat following. Both offer nice health club facilities, tour and transportation desks, and gift shops. Staff are fluent English speakers.
In terms of location, the Grand is directly on Tverskaya, the main shopping street, about 15 blocks (30 minute walk from Red Square). The Royal is in on a more quiet street about 4 blocks from the Bolshoi and 8 from Red Square.
You can't go wrong with either hotel. If I were in Moscow on business I would choose the Grand because of it's more business like atmosphere and direct walk out onto busy Tverskaya. If I were on vacation I would go for the Royals' more "romantic", relaxed, intimate feel.
[This message has been edited by edsh (edited 05-29-2001).]