We had a wonderful experience and the treatments were excellent. The only negative I could note would be the cleanliness of the spa area, there were areas that needed cleaned - eg, Hair clumps on the floor of the thermal shower and some dirt marks in the saunarium but it didn't damper the experience. Overall we still had a wonderful day and the staff were very friendly.
We had a nice experience while it was still quiet - I would recommend going earlier as the changing room gets very cramped with more than a handful of guests, and the spa area can get quite noisy. Basic spa etiquette was not always followed by guests e.g. keeping sauna/steam room doors closed. However, the spa itself is lovely and kept clean.