To answer the the OP, I've used wb270 for 15+years or so and it was my original source of service providers - I then branched out and now use it for intel, more than SPs.
In my experience, the girls on wb270 travel alone, cater predominantly for guys with a muscle/wrestling fetish, work back2back sessions and typically offer domination, wrestling, muscle worship and HJ. In my experience, some will offer RO at their discretion but not advertise it. I've had FS with a few girls on wb270 but I knew in advance it was on offer (I asked directly - having got info from specialist forums).
I'm with the other posters on this thread, that the best options in London based on price and service are established WGs who also happen to be muscular.