I have visited london submissive girls twice and both times have been very satisfying.
The first time I called and asked if the girl was ticklish and was given a truthfull answer.
The location seem safe. The receptionist was friendly and relaxed. The playroom is downstairs and is clean and - very important - contains bondage gear suitable for women. It’s not very big, and i think the only furniture suitable for tickling are the bed and a cross (and the floor).
Note that in addition to the hourly rate there is a charge of 40 gbp for bondage. It’s also customary to tip “the maid” about 20 gbp (may have changed). You give all monye, including the tip to the girl herself after you have talked about the session. When you call to make the booking, you only give them the name of the girl and how long your visit will be.
Have fun, if you go.