I think we had a box, which didn't work for the old Appy, but wondered if it has worked for anyone? It is the "smell" based calmer. If I can find it I may try it for the younger Appy who is having an issue with an abscess!
The reaction to pax is very variable and I wouldn't really class it as a calmer. One of my mares was very difficult to catch and I sprayed pax on me, it works on people smell, she suddenly stopped trotting round me in circles and walked up to me sniffing the pax and willingly let me catch her! I was very impressed but my other mares didn't react to it at all, they however were never standoffish in the first place. In my experience it didn't work well with gelding.