I visited in April. A beautiful hotel in a perfect location for the Monte Carlo Masters. Please be aware that the beautiful lagoon area is not open before May, despite the very warm weather. Dining options are limited and extortionate, but they allow takeaways and deliveries to your room from other places, and are located close to excellent Larvotto Beach restaurants.
The express bus transfer from the airport doesn’t go to, or near, the hotel during the Tennis Masters or any major event, so arrange alternate transport. Helicopter costs little more than a taxi.
Wonderful for the quiet beachfront area, but as far as possible from the rest of Monaco.
Rooms are beautiful, balconies huge, staff efficient.
I would stay here again for the tennis, but elsewhere to be in the heart of the principality.