I've not met any of them but if you met Alexandra in Mornington Crescent then it was at the flat rented by Samantha T Black. She's moved on and Alexandra is now based in Piccadilly. If you wish to combine domination with personal services, then I recommend Samantha (Ginna) Black, Alex from the London Retreat and Rubberlust from AW.
Rubberlust, aka Mistress Chatterley, looks much better facially than her pictures because trying to look stern ruins the shots. Combining GFE and domination with her is 250 per hour.
The other two are 200 per hour but I'm not sure if Ginna charges more for a dungeon. She would probably use Alexandra's. For pictures of Ginna, search Goddess Ginette images on Bing.
The reason why I don't review on here is that according to some girls I release what they feel as electricity and that introduces an element which will not make my experiences similar to those of other punters.
DF