I had 3 TC20 cooking heroes for ~4 months. Call it (120 days/2 days) * 3 TC = ~180 pulls
I am very happy with the results. The camps have given me so far:
5* ( x8 ) (Joon, Magni, Lianna, Sartana, Khagan, 2 Thorne, Quintus)
4* ( x31 )
3* ( Lots ~140)