Assuming this is the 6 Duke Street place, I have been here previously yes and would say that it is well worth a visit.
I went lunchtime (some months ago now) and had a good massage from a 40 something masseuse. She didn't look amazing with clothes on but actually had a very fit bod and some cracking boobs. Was able to play with them and massage was ok, credit card swipes were good etc.
Shower not amazing. Shop upstairs felt pretty legit but was all good downstairs.
YMMV of course but I was impressed. Think it was £45 (may have been 40) plus £40 for B2B so not cheap but it is Richmond.