They tend to melt from the heat of the lamp. Then they don't work so well. The only solution is to replace them. They are kind of expensive from the dealer ($56). If there is a junkyard near you or someone parting out a convertible, that's a cheaper route.
Only convertibles. Any 9-3, and I think NG900 should do to. . However, you do need to color match ... assuming you care. They come in beige, gray, and black. They have different part #'s for beige and gray for the 9-3 because those shades varied in color. Black is black.