My husband and I stayed at Le Marquis for a trip to St. Martin in February, 2011, and it is hard to think of any "cons" about the place. The rooms were clean and well-kept, and very spacious; I think every room in the hotel has a beautiful view of the bay, and a private terrace. It feels very luxurious.
Le Marquis is up a steep hill from the main road - about five minutes in a car from the bottom to the hotel. However, the Radisson is halfway between the two, and while Le Marquis is not directly on a beach, the Radisson is, so it's a very quick jaunt (by free shuttle) to the sand. There is a lovely fitness center, and tennis courts, as well as a small pool at le Marquis; the Radisson below has shopping, dining, and both pool and hot tub.
The hotel is situated right near Grand Case, which has the best dining on the French side; we went there almost nightly for dinner, assisted by the marvellous staff.
The staff were so cheerful and professional; you truly felt like it was a joy to them to help you out with something. I have never before stayed somewhere where I was so well and kindly taken care of as here, and I'd recommend it without hesitation to anyone going to St. Martin. The only downsides I can think of are that one needs a shuttle ride to get to the beach (see above) and there is no kitchen on-site; a lovely cold meal is provided for breakfast, but this is not an American Plan type of place, and you'll have to go out for lunch or dinner (or they'll get it for you, but it may get chilled on the trip). This, to me, was not a downside, but I know some folks are looking for an all-inclusive, never have to leave my hotel, type place.
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