Hello Josilyn,
I had a BA on 7/12/2017, 555 cohesive silicone half under the muscle. The incision is in the breast fold. I was an A cup and 40 band (39 inches) and wore a sports bra. I did not fill a top to my liking and felt self conscious. I am now a full C and Dr. McGinn said that is a large as I could go.
Dr. McGinn spent 2 hours in the operating room working on me. She had to make a breast pocket and she managed to do 1/2 of each implant under the muscle, that will help hold them into place, she said.
I will lose an additional 16 pounds (24 pounds down) and hope to get to a 38 band. At 180 I will evaluate my tummy, hip breast measurements and see if I need to lose additional weight. I think I can go down to 165 to 170 but only if it makes a positive difference. My boobs will not deflate

I love how I fill a top now. I have not been on a beach this summer ( I really need a three day B&B stay at the beach) but I can feel better about my body now that I have a bust.
I obsessed about the implant size. I was supposed to have my BA Nov 15, 2016 with my GCS but due to a complication I had it 6 months later on July 12, 2017. In November I was obsessing on the GCS and the surgery issues I was facing. I was not thinking about the BA. Post GCS and 6 months I watched every Utube video and post there was about a BA. I was obsessing to the maximum.
Mentor makes up to 800 cc and Dr. McGinn recommended a 555 and said It would have to be over the muscle. It turned out to go partially under the muscle and the doctor had a difficult time with the right side. I am East West and have a wide chest to no cleavage without a BRA and I need to wear a sports bra for 2 months 6 days. Also I keep wearing the ace bandage under the boobs for another 6 days. The sports bra and ace bandage are on 24/7 except for showering.
I was 327 pounds at one time (perhaps higher because I stopped weighing myself at a point. I had to use a cargo scale on the loading dock and it was really embarrassing) so I have skin that is plentiful, not loose but not tight ( I almost stopped eating for 6 months and exercised every day. I had to drop the weight and when I did the skin responded very well). So there is no issue of the implant going into the pocket the doctor made. There is a potential issue with stressing the incisions that make the breast fold. I need a strong capsule around the implants before I do any bouncing or there is a chance the implant could break the stitches and slide down. So I follow the doctors orders.
A trans BA is different than a Cis BA and Dr. McGinn explained the Cis have a breast pocket while trans need a pocket made.
I am really happy I had the surgery and the size that was chosen. If they were bigger then moving my arm out front would take more of an angular motion. I am big enough for my intent (feel better about myself) and not too big as to make a potential issue with my anatomy.
A guy I know sat next to me when I was eating lunch with several others. He sat there and said I should have gone bigger. He kept it up and said I can hardly see them and repeated it several times. I looked over and said, thank you. You have made me feel so much better about myself. He stopped, looked down and left. None of the other people at the table said anything. Some people are so preoccupied with breasts. I decided to eat my wrap at my desk this week and walk for lunch. Perhaps I will do that the rest of the summer and fall.
It is funny to see guys sneaking a glance and looking embarrassed when I make eye contact with them afterwards. One guy at work I know well said I look good and it really made a positive difference. He was red in the face when he said it and it was precious. He is very cute and self confident; yet, he was embarrassed. I felt so good when he said that. There are some really nice people in the world.
I have had several woman comment positively about my size choice and how they look

It is funny how breasts affect guys. I always wanted the figure and compared how breast looked for what I hoped I would look like on HRT. I grew an A cup and my breasts were somewhat conical. Now I have a full C and when I can wear a regular bra my breast will fluff up a bit and overall look bigger. My breasts are soft and feel really good. I have some nipple soreness from the sports bra on one side and the implant on the other side. The poor nipples can not get any relief. I do notice my nipples are erect so much more now, almost always. I had several woman comment about showing and when can I wear a regular bra. I wear a lot of floral prints at work which helps camouflage things. All my tops still fit, so so happy.
I hope this helps.