To the original poster's question: I agree with what my friend MadArtist said above. I have not personally taken bioidenticals 'yet', but I plan on it. What I do know is that this is not a one time deal process, like doctors do with conventional medicine, or the one-pill-fits-all system of medicating. It is imperative to monitor the body's fluctuations and changing needs. Going for four years with the same dosage is very likely to produce discomfort somewhere along the line. For this reason, biodentical supplementation is not an inexpensive process, but if your budget allows it, it sounds to me like it's worth every penny.
I do know some women on it that feel they have gotten their lives and personality back with these little helpers.
Here is a page that I hope will give you some more information on this subject. Bon Chance.