I grew Hoya deykeae in my regular mix, but it seemed really susceptible to over-watering.  It does not grow nearly as easily as H. callistophylla, but is less difficult than Hoya sp. gunung gading.  It can turn on a dime; one day it will look like it is thriving and the next can look like its on death’s doorstep.  A wrong watering move will make several leaves turn yellow, look jaundiced and eventually fall off.