I have been on steady HRT for about 4 years now (Estradiol Inj. & Spironolactone ) and the changes depend largely on the individual (health, diet, age etc.)
I would have to say, while there has been noticeable breast growth, the biggest physical changes have been, softening of the skin and the reposition of fat, especially around the middle and back side.
That being said, HRT is a very slow process, and most of the time you will not notice much of a difference at all. Not saying that there isn't changes, just that their so slow that it's difficult to notice them, especially at more advanced ages.
However, the biggest change for me is emotional. From about 6 months to a year, I had noticed that I was significantly less prone to anger. Of course, I would still get upset at stuff, but instant displays of anger or rage gave way mostly to first thinking "was that thing that used to get me super angry right away, really worth my time?"
In addition to the reduction of anger was the increased moments of sadness at things that I used to not even think of before. It's not that I cry for no reason at all, but I am much more likely to feel emotional sadness about things that used to not bother me or did bother me but I was able to cover them up.
All in all, HRT has helped me to feel some of the things that used to be a big part of me when I was a child, but had found ways to hide them through the years.
In that way, HRT is an amazing experience.
Katie