The thing to consider about moss is that it tends to be a wet medium. It's perfect for orchids that need constant, even moisture, but it is absolutely detrimental to plants that like drying out or need air circulation at their roots. And, unlike bark, it tends to accumulate salts more readily, and so needs to be changed often.
Moss works best in baskets, where it can dry out more quickly, and where you can check the moisture more easily. I haven't had good results putting plants in clay pots with sphag. I've had rot problems due to excess moisture using that system.