I know this thread is focused on reviewing the ladies but I thought I would do something a little left wing and share a list reviewing the environment of the actual spas that I have been to. I know things like the environment, privacy and cleanliness is important to some people so thought this would be helpful.

Joey Spa: Clean, well maintained, excellent interior, good facilities and spacious shower cubicles. Showers are very good. Decent privacy, no security guard downstairs and no waiting room. Real towels.⭐⭐⭐⭐⭐

Wish Spa: Clean, well maintained, excellent interior, good facilities including a very spacious bath tub / shower area. Showers work perfectly. Decent privacy and no waiting room. Rooms are slightly dimmed but they don't over do it. There is a security guard downstairs. Real towels. ⭐⭐⭐⭐⭐

Kiss Me Spa: Fairly clean and generally well maintained. Rooms are generally decent sized with double bed in each room and mirrors. Normal towel. Large waiting room and no security guard. Rooms are quite dim. In a busy area but discreet enough.  Real towels. ⭐⭐⭐⭐

Rose Spa: Clean. Rooms are on the small size as are the showers but enough to fit two people in. Single bed in most rooms. Normal towel. Large waiting room and desk. Well maintained and good interior. Rooms are quite dim. Discrete part of Wan Chai. However there is a security guard downstairs that sometimes asks you what floor you are going to. Real towels and they sometimes even leave a rose on top of your towel. ⭐⭐⭐⭐

Afterwork Spa: Fairly clean, showers are a decent size. However they often will smoke in the rooms by the window with ashtrays on the shelf and ledge so some rooms.do smell (esp Room 2). Some rooms have beds but others don't and just have a mattress on the floor. Uses single use towels. Lighting is good as they don't over dim the rooms. Privacy is okay, there is a security guard downstairs. No waiting room. I believe they do actually have a cleaner on site as I have seen her before. ⭐⭐⭐

AT Spa: Fairly clean and decent sized rooms. On the dim side in terms of lighting. No security downstairs but there is a waiting room upstairs. Normal towels. The showers are decent and some have a bath tub which seems defunct. ⭐⭐⭐

Fantasy Spa: Rooms could be cleaner and walls are quite worn out, but big enough. Signs of mold. Rooms are very dim. Showers are acceptable and good performance. There is a large waiting room but no security downstairs. Normal towels. ⭐⭐

Hot Spa: Quite rundown with holes in some walls where someone has probably punched it and not much room, but decent shower and there is a waiting room. Not good for privacy since it is right next to a Taobao collection point. ⭐⭐

Do you agree? Welcome your comments.

A few additional points (not meaning to steal your thunder in any way, just contributing lol)

K2/Mia: I'm sure all would agree that K2/Mia really tops in terms of facilities, but maybe its best you left them out to make it a fair comparison lol
AT Spa: They actually have two locations (from what I'm aware), their main one you mentioned I agree, their other is actually a bit nicer.
Kawaii: I've only been to the one close to kissme, but I would give that a 4-star, Japanese style that isn't too bad (though last I saw was aging a bit)
Lady spa: I've frequented here and would say their locations are 4-star, a bit old but clean, good shower size.
Luna: I would give it 3, small and a bit old for my liking, but some are okay with it

There are a few popular ones like Nuru spa, HK Spa and Nice Place, but I have yet to try, hope other bros can contribute.

I would add Imperial Spa in TST, one of the last remaining 'old guard' spas with an actual reception and an area with large sofas and television where you can get foot/thigh massages and ear cleaning done. It's almost like half a sauna. The actual rooms are pretty clean and they renovated not too long ago.

M2 Spa in Wanchai has pretty good facilities also. New and clean. The room I tried was not as spacious as K2 but the standing shower was good.

@wingardium: Oriental Spa is a full fledged old school type sauna with complete facilities like a jacuzzi area and food service. On the other hand Imperial Spa is still considered a walk-up spa so I think they fall under different categories. If you want the traditional sauna experience then Oriental Spa is the way to go. If you predominantly want a massage but also appreciate having a reception and lounge area to hang around for a bit with supplemental services (e.g. ear cleaning) then Imperial Spa would be the better option.