So I've been on hormones pretty regularly (except for times I forget to place a refill order and have to wait between shipments) for about 6 years now. I have a prescription, but because I am self-insured and have to worry about potentially being dropped by my health insurance for any little thing, I order my hormones from overseas, and I adjust my dosage myself. While I am somewhat buoyed every time I read that some more major companies now have health insurance policies that cover transsexual top and bottom surgeries, it pisses me off that this has no effect whatsoever on me, because as an individual, I have absolutely zero bargaining power and would have to pay astronomical premiums to have a policy that covers such procedures.
Anyway, based on research on normal hormone levels, and the way they change over the course of the day, I've pretty much settled on an alternating day schedule of taking 6 mg of beta-estradiol at night (at the upper limit of recommended dosage), and the next day, I take an anti-androgen (dutasteride seems to work best for me) in the morning and 4 mg of the estradiol at night. One week each month I also take progesterone with the estradiol each evening. This has worked pretty well for me - I think my genetics limit my breast growth to what meager assets I have now (barely fill a 38A bra) - based on a hard-to-define feeling of "rightness" with my body. I can definitely tell if I've skipped a couple days because I let my drugs run out and have to wait for the next shipment.
Having said all that, knowing in my head that I am very careful about knowing how my body usually feels, and keeping in good physical shape, every spring and fall when my seasonal allergies give me horrific sinus headaches, I occasionally am seized by somewhat irrational fears that the estrogen is going to give me a stroke, and I'll have to go off the E, and I'll be depressed and masculine again. I flash back to an early episode of Chicago Hope (a medical drama that started on CBS about the same time as ER did on NBC, but didn't last very long). Mia Sara (you probably know her as Sloane from Ferris Bueller's Day Off) played a transsexual whose hormone therapy was causing her medical problems, and the episode ends with her suicide or attempted suicide (I can't remember) because she didn't want to keep living while fighting her body's re-masculinization. There were all kinds of medical inaccuracies in that show mostly due to the need for time compression in a show like that, but it definitely struck a chord with me. I start thinking about losing some (though not all) of my breast growth, and to be honest, that's actually secondary to a change in my mindset when on hormones. Going back to having a "purely" male body and hormones would be extremely depressing. No, I'm not suicidal, but it is sort of funny that something as relatively minor as seasonal allergies can send my mind into such a crazy stream of fears.