Ive had a reduction. I am aware that I got off easy on the scarring. The underneath has a scar, but it's not raised. The anchor part down from the nipple is invisible on one and the other not so much, but my husband thought it was a birth mark until explained. It's flat, too, but has a pink splotch.
I went from undetermined size (around a 36F or FF or whatever depending on what store I went to, crazy sizes) to a D cup. It was amazing. I've suffered life long back issues. I had this done at 21. I'm finally over the back stuff at 34, for the most part. This included years of care and surgery for my back because of a broken off piece of disc. I'm very active now. I run. I lift. I can do day to day things without the severe pain I'd get in my younger days. I would have been more active, but those suckers made everything impossible.
The real drawback for me was finding out that some of my milk ducts were severed. When I had a baby I did produce milk, but not all of it had a way to get out. I didn't realize so for three weeks I tried so hard. I finally had a lactation consultant tell me the hard truth that I wasn't ever going to make enough milk to feed my baby. I had to give up. It was really painful, too. Like my body wanted to make the milk, and some of the milk could get out, but the rest wasn't, so it was sending signals to dry up. But the use of some, plus the act sent messages to make more. I imagined my breasts were engines running with no oil... I can only describe it as a very tight and very burning sensation. Like boobs on fire. I don't think I'd have made the decision to keep the originals even knowing what I know now. I wasn't happy. I was in pain. That seems like a small price to pay.
However, some women need to hear that. I'm pretty sure implants have far fewer risks in that area, but if you're ever considering using your boobs for more than just ornamental value, it is something to talk over with your physician.
10/10 would do again though. And again, scarring on me was amazingly minimal. Compared to some images I've seen, I feel like I got off really easy.