I had mine pierced after college, maybe five years before my first was born. The left one began to be rejected and grow out so I took it out after less than a year. I had originally intended to remove the remaining one for feedings, but keep it. However I never did buy easier to remove hardware, so I scrapped that plan. I kept the piercing in through labor and only removed it just before attempting to nurse for the first time.
I had slight difficulty nursing on the left side. The nipple on that side is tougher and has more scar tissue that makes it a bit lopsided, but it still works. Between the right side being more "normal" and easier adjust to, probably mostly due to the fact that I'm right handed, I do use it more, but they both work. Milk does come out the holes, but not as badly for me as some others have said. It doesn't shoot out of them, it's just another outlet. Even with over active letdown, the milk still comes out the usual way, there is no spraying out through the holes.
If I were to go back, I probably wouldn't have had them pierced in the first place.
