Digging this old thread up since I live/work in Kuwait and have had lots of experiences at all three MR-branded hotels over the last few weeks, months and years. Thoughts on each below:

General notes

• All three hotels are owned by a major Kuwait-based real estate company called Salhia Real Estate Company.
• Aside from the two legacy Starwood-branded properties that are now part of the Marriott fold [Sheraton Kuwait, A Luxury Collection Hotel, and Four Points by Sheraton Kuwait], there is a Marriott Executive Apartments due to open in a new, Salhia-developed mixed-use complex in downtown Kuwait in 2020.

JW Marriott Kuwait City

• Formerly the Le Méridien between 1981 and 2002. City-center location close to the National Assembly, government ministries and waterfront.
• Overall style is quite dated but they're allegedly doing a soft renovation of the rooms. Haven't quite been able to ascertain what that entails.
• The Crossroads restaurant in the lobby is the new all-day dining venue; totally renovated and modern.
• Food in general is a strong point in this hotel and across the board in Kuwait. The Kei Japanese restaurant is very popular - pricey but excellent.
• Health facilities are fine - decent gym and a nice if smallish indoor pool. Sun deck is a bit of a joke since it doesn't get much sun and is clearly an afterthought. [Fun fact: the pool used to be on the top floor where the large windows are, and had an island in the middle that doubled up as a nightclub back in the 80s.]
• Kuwait City isn't very pedestrian-friendly or attractive, so the attached luxury mall offers a chance to stretch your legs.
• Yes, there IS a large cemetery adjacent to and behind the hotel. It's mostly just sand at this point, but there are many small headstones so if you're not keen on this view, be sure to mention it at the reception.

Courtyard Kuwait City

• Quite possibly the nicest Courtyard in the entire Marriott system - it bewilders me how this isn't branded as a full-service Marriott, Renaissance - or - after the Starwood acquisition, a Westin or Le Méridien.
• The hotel was built in 2003 and just completed a soft renovation that swapped the carpets, curtains and furniture upholstery out in the rooms to change the overall color scheme from yellow and green to grey and silver. Bathrooms receive modest updates with the addition of hand-held bidet showers.
• Excellent breakfast spread in the beautiful, airy Atrium restaurant. Sushi Japanese restaurant is quite nice but Soul & Spice has some of the best Indian food in Kuwait.
• Service across the board is very professional, friendly and genuine - a bit better than at the JW Marriott, dare I say.
• Very decent, sunny pool and Jacuzzi on the lower building's rooftop. Gym is in good shape.
• Platinum treatment is great: executive lounge access (in a Courtyard!) with breakfast/all-day snacks, suite upgrade and fresh fruit basket delivered to the room.
• The hotel is connected to an upscale mall with shops and restaurants [try Burger Boutique if you're a fan of burgers], and there is also a shaded outdoor plaza with a great coffee joint.

Residence Inn Kuwait City

• The newest Marriott on the block having opened in 2014. Location is a bit odd since it's next to a major hospital, diabetes facility and school, but it is a half-block from the seafront and Souk Sharq mall so you can go for a walk if you're keen to cross Arabian Gulf Street.
• Clean, modern design overall with Arabesque touches here and there. Big windows in the lobby and rooms to allow lots of light in.
• Very nice, modern, spacious studios and apartments. I've consistently had studios during my stays here and found them to very well furnished and laid out with everything you could need. Bathrooms are roomy and have large shower stalls.
• Breakfast, as usual, is included and is excellent, with cooked-to-order eggs and a very wide variety. The one on-property restaurant is also open for lunch and dinner. [Hot tip: there is a dumpy hotel called City Suites just down the street from the Residence Inn with a fabulous Thai restaurant called Oriental Cuisine. Try it if you're a fan of Thai cooking - possibly the best in the country.]
• Platinum upgrades a bit hard to come by since this IS a Residence Inn, but after a bit of haggling I managed to get one of the awesome studios at the end of each floor that are elongated in layout but have two corner walls of floor-to-ceiling windows, a great sea view and tons of natural light.
• There is a gym and sauna on the property, but no pool. The hotel offers a complimentary shuttle to the nearby Courtyard if you wish to use the pool there.

Although I would personally rank them (1) Courtyard, (2) Residence Inn and (3) JW Marriott, you can't really go wrong with any depending on what you're after. They're all well-run, staff are great and they're decently located.

Happy to help shed more light on any other issues/concerns/questions anyone might have.

khabah