You will be very happy with PVCcages.com. They make excellent cages. They also hold heat and humidity very well. For the chondro, I would definately go with a radiant heat panel. If you were to put ball pythons in PVC cages, you could go with flexwatt if your room is above 75F or radaint heat panels if your room is below. However, it is my opinion that ball pythons would do better in rack systems, as opposed to cages.