The PPO is probably most expensive but also probably has the most flexibility as to who will honor it. You get to choose who you want as a doctor rather than having to fit into a plan or choose from an approved list. I would read the sections in the three plans as to what they cover for psychotherapy (often there's a "separate" book for that, ask your plans administrator at work) and their list of doctors, etc. It could come down to how big an area you live in; if you're in the "country" finding a therapist you like and can work with could be harder if there's not many to choose from one a list. If you're in a larger metropolitan area though, one of the less expensive plans might do fine.