We booked a tour with this included in the package. However, it turned out that we just passed by here and we were not able to experience what a "poring hotspring" is.
There were many pools but it was still too crowded. Probably ten people needs to fit in just a pool for 4. This is not okay for foreigners travelling to just relax.
Probably, the management may need to limit the number of visitors per day. Like for us, we paid in advanced but we're not able to experience it.