I started HRT with pills for both estrogens and anti-androgens. Oral estradiol taken sublingually for the estrogen, spironolactone for the anti-androgen. Still on spironolactone for the AA, but I have switched to intramuscular estradiol valerate injections.
In my opinion, the injections are superior in many ways.
I switched because I had heard from many people that the injections provided better results. I definitely would confirm this for myself, although your mileage may vary, don't expect total miracles or anything. All I did was ask my doctor if I could switch, and he agreed to try it out.
Week 1 of HRT on pills-only, I started getting breast pain, discomfort, soreness/tenderness, heat, etc. Then it kind of faded. That and everything the pills did to me were nothing compared to what the injections did. I have had so much breast growth since I started the injections. My roommate has commented, without me saying anything about it, that my breasts have definitely grown a lot since she moved in 3 months ago. I let my ex-gf, who I'm on very good terms with, feel them the other day, and she was pretty surprised - they were bigger than hers. (I was in guy mode at the time and hiding them)
In mere hours I will be injecting myself again, for the 11th time. Just 11 weeks, and I've had so much change physically and mentally. Everyone is amazed when they see my pre-hrt pictures. My ex, my family, my friends, my coworkers - and I'm 4 months into HRT. 2.5 months of that was with injections. Soon to be 2.75