I've only had to replace one tag in one of my goats, and that's because the breeder put it in upside down, with the male bit sticking out the back of the ear, so the female bit was snapped off it, but the male tag was still hanging through the ear, no damage to the ear. I got shearwells set eid tags for the lambs and kids, and had no lost tags in any of them this year. Eid optional, but easier and cheaper for me with 3 breeding goats this year to just get the eid for both lots.