It also depends on the time slots a girl offers.
Any WG offering 15 and 30 min sessions is going to be meeting a LOT more guys on a daily basis than an 'hour minimum' girl.
I've been told wildly differing stories about numbers on many occasions, but a safe assumption seems to be '5 is good', but '8 is better'.
On a mental day, some girls can 'do' 20+ ...