This thread refers to the various Marriott brands within a specific geographic area. Marriott Bonvoy hotels in Hong Kong usually have posts asking which property is better, etc. Trip reports are usually better suited in the property specific threads

Broad summary of the Hong Kong Marriott brands is as follows:

Luxury
The Ritz-Carlton, Hong Kong - Superb full harbour views, good quality restaurants on-site and the world's highest bar (Ozone, that has up to a 20% discount for elite members that actually makes it reasonable value). Negatives would be price and location is in Kowloon (i.e. not ideal for tourists).
St Regis Hong Kong - New (in 2020), great quality rooms, excellent service in the hotel and restaurants, views are more standard and location is a little less convenient, but on the Island in Wan Chai and near the Exhibition Centre. Hotel restaurant l'envol offers quality French service and food and has two Michellin stars. Near the newly opened (2022) Exhibition MTR station with walking under cover (one stop from Admiralty or Hung Hom), or walk from Wan Chai (approx 10 minutes).

Mid-range
JW Marriott Hotel Hong Kong - Ideally placed for tourism and likely business, built in an MTR complex with a luxury mall underneath. Small rooms with a good view of either the harbour or a hillside, but compensated with an excellent lounge and breakfast. Somewhere to spend time outside of the room. Not hugely changed since 1980 but a classic hotel with excellent on-site restaurants and a newly renovated/larger lounge than the version prior to COVID.
W Hong Kong - Quirky, next to the Ritz Carlton and with an outdoor pool. On-site restaurants are more limited but in a good location. A nice alternative to the Ritz if you want to explore Kowloon, or are under 30. Good weekend champagne brunch.
Renaissance Hong Kong Harbour View Hotel - More of a convention centre hotel, but with nice uninterrupted harbour views and reasonable room sizes. A little far from public transport but with walkways to get you to Wan Chai or Exhibition Centre MTR stations fairly rapidly (mostly under air-con).
Sheraton Hong Kong Hotel & Towers - Huge hotel that historically had a separate "Towers" side (now being removed) and one of the worst lounges in the Marriott network (now improved) with poor elite recognition, but relatively large rooms and close to public transport, museums, shopping in Kowloon and the star ferry. Has had an ongoing refurbishment from late 2022 that appears to be addressing historic quality problems, but this is underway as the wiki is updated. As of March 2023, the "lounge" is on the second floor opposite the reception desk. It's open noon to 6:30pm only, with cocktails/food from 4:30pm-6:30pm and guests are allowed in for only one hour (enforced). There is no lounge opportunity for evening dessert/coffee.
Le Meriden Cyberport - Large rooms, nice staff, in the middle of nowhere (by HK standards) and very consistent brand standard, including a lounge. You will need to get a taxi to any sight or location unless you are visiting the tech companies in the area. Refurbished and reopened in November 2022, and has a shuttle to the Airport Express MTR/Central once an hour.
Hong Kong SkyCity Marriott Hotel - Next to the airport, far away from the city (on the MTR or Airport express via a shuttle bus) but excellent evening buffet and ideal to explore Lantau or visit friends (aircrew) in Tung Chung. You can't walk to the airport due to ongoing construction work, even if it looks like it is only a 5 minute walk, it isn't.
Hong Kong Ocean Park Marriott Hotel - Huge pool and ideal for children. Rebranded to a resort to limit elite benefits. Worthwhile for a long weekend away or when visiting Ocean Park. Close to the (less convenient) Ocean Park MTR for tourists. Good restaurants on-site, not much in the local area.
Sheraton Hong Kong Tung Chung Hotel - New hotel that opened in December 2020, more designed for shopping or being close to the airport (via taxi or hourly shuttle bus), good facilities and pool. Far away from the city centre in a residential area.

Boutique
The Mira Hong Kong, a Member of Design Hotels™ - Not so close to public transport (approx 10 minute walk from Tsim Sha Tsui MTR), limited elite recognition but good for the bars of Tsim Sha Tsui (TST) and Kowloon. A better place to head to after a day of shopping in Kowloon or a heavy night out in TST.
Mira Moon Hong Kong, a Member of Design Hotels™ - Close to the shopping of Causeway bay, good rabbit based romantic hotel with sizeable bathrooms and real baths but limited restaurant facilities in-house. Refurbished in July 2022.
The Park Lane Hong Kong, Autograph Collection - New, and not yet opened. In 2025 it is expected that we will get a new Autograph, a conversion from the current Park Lane Hotel, Pullman. The hotel has a great bar and view. Let's see what happens

Value
Courtyard Hong Kong Sha Tin - generally agreed to be the best value Marriott in town with an excellent executive lounge, great value rooms and good elite service. However far from town (45+ minutes on public transport) and designed for those who want to visit Sai Kung or relatives in the new territories.
Hong Kong Island Hotel | Courtyard Hong Kong - Reasonable location and good value business hotel that isn't that far from central or the MTR, but is ultimately not very distinctive. Offers a good breakfast for elites and a small executive lounge more focused on drinks than food.
Ovolo Southside, Hong Kong, a Member of Design Hotels™ - Excellent value and close to Ocean Park. Near the MTR and with a well respected local Mexican restaurant. Offers a 3 hour social hour (free flow with food) if you book direct, a hidden gem. At points has been fully vegetarian as well.
Four Points by Sheraton Hong Kong, Tung Chung - A combined building with the Sheraton Tung Chung, so very similar with some shared facilities but more basic rooms.

Typical responses from those who live in Hong Kong:
I want the best hotel money can buy: Ritz Carlton (views) or St Regis (service)
I want to save money: Ovolo Southside (qirky) or Courtyard Sha Tin (far away)
For business: JW Marriott (Hong Kong Island) and W Hotel (Kowloon)
Airport Stopover: The Sky City Marriott is in the airport complex (accessed via shuttle bus) but realistically you could head to the Ritz Carlton or W Hotel on the airport express in under 30 minutes. Alternatively the Sheraton Tung Chung, and cheaper Four Points may offer more reasonable rates and are only 10 minutes taxi to the airport in an area where a lot of Cathay staff live, or use the airport shuttle bus (link).
Theme parks: Disney is not close and arguably the Sky City Marriott or Sheraton Tung Chung/Four Points Tung Chung are closest, but would need a taxi. Staying at the W or Ritz Carlton may be preferable and using the MTR to get to the park (one change). For Ocean Park you have the Ocean Park Marriott (Resort) or Ovolo Southside within walking distance or the JW Marriott is only one MTR(metro) stop away and more central for other sights.
Staycation: Ritz Carton (on-site restaurants), St Regis (service, two good if pricey restaurants), Courtyard Sha Tin (bargain) or the Ocean Park Marriott (pool for children)
Space: Le Meriden Cyberport, but only because it's in the middle of nowhere (though this is subjective, as it's about 20 minutes in a taxi to central)...
Undiscovered gem: Maybe the Ovolo Southside but ultimately this is Hong Kong so you can't really expect a bargain, it's an efficient capitalist market after all!....

**Staying in China**
Note (pre-COVID) you could save serious (USD100s+) by staying in Shenzhen though this would involve crossing an international border and would only work for those who wanted to visit China and had a visa. With the border reopening this is an option, for example the St Regis Shenzhen is typically great value with free-flow executive lounge privileges on the 100+ floor or staying at the Four Points in Shenzhen is less than a round of drinks in Hong Kong and offers an unlimited dim-sum lunch for less than 20USD pp. Getting a visa isn't as easy as pre COVID though, and the China "visa on arrival" scheme can be over subscribed, leading to long queues. If you have a China Visa though this could still be an option, though it will take approximately 2 hours to get from the Shenzhen StR to the centre of Hong Kong (made up of approximately 20 minutes metro in Shenzhen, up to one hour of border/visa processing time, then 40 minutes on the MTR to Admiralty station)

**Quarantine FYI**
In December 2020 the Hong Kong government agreed a list of quarantine only hotels for what became part of the world's strictest quarantine regimes with at points any person entering HK needing to spend 3 weeks in a hotel. A number of Marriott hotels took part in this programme at varying points until hotel quarantine was removed in late 2022. The "new" Four Points in Tung Chung didn't open for normal guests until after the end of quarantine, and at time others were on/off the list, including the high end W, then the Ocean Park Marriott, Renaissance, Ovolo, Mira Moon and so on. Of the Marriott brands, only the JW Marriott and Ritz Carlton never took part.