I started Abi/Pregnisone in June of this year and started the Estradiol patch a day or two earlier, the same day I started radiation treatment. I had a rough first month (fatigue, pressure in my head etc), but I think it's impossible to disentangle my symptoms from the various treatments. I think most men on Abi/Pregnisone will also be on an ADT drug, so again, it's hard to know which treatment is causing the symptoms.
Exercise made a huge difference in combatting the symptoms.
In my 2 monthly tests so far, PSA is <0.006 and T is <3. Some other blood values are either slightly out of range or on the border of out of range, but since Labcorp has great data analysis tools, I realized I had similar out of range values before treatment, for some, but not all of the values.
For the last few months I have felt pretty close to my old self, although my biking stamina has decreased to some extent. Also I used to sleep through the night most nights. Now I get up once and occasionally twice and I realize I am not sleeping as deeply as I was before. But that is improving as well, and again is the fact that I get up more from the drugs or radiation?
Good luck with making a decision and I hope whatever you choose works well for you.