Not extremely noticable, no.
It varies per woman though.
AND it can vary per breast. My right nipple is my FUN nipple.
My left nipple is a bit less responsive...and time also is a factor.
After many years, I still seem to be re-developing sensation in my breasts.
Also the type of surgery can make a big difference. In one kind the nipple is actually REMOVED and grafted back on, and the other surgery all the blood flow is retained in the nipple and much more sensitivity remains. I had the latter.
It was well worth it but after a period of many years, you will still have the *shadows* from where your breasts used to hang (kind of fun to see how LOW they went LOL)
and you'll have a chest wall that is accustomed muscle-wise to HOLDING those breasts...so there can be a funny ridge.
I can try to take a photo for you if you'd like, so you can see what I mean.