L.D.
Usually people with implants do fine as long as the ducts were mangeled in the process. The baby may have a harder time latching on because you breast are firmer than they would be otherwise.
To answer you new question about what happens. I don't know about saging but I have heard of the implants moving. I guess when the milk ducts are full there may not be enough room for them to expand so the implant will move. I've heard of implants moving up into the shoulder area or armpit area. I think this is pretty rare.