I am!
It started out terrible - S. would only want milk when Z. was nursing, and I couldn't nurse them at the same time because Z's been choking on milk if I don't have her in precisely the right position (and sometimes even if I do). Now S. is at the point where she knows she has to wait if Z. is nursing, and sometimes if S. is nursing and Z. wakes up, S. knows she will have to "finish up".
So...I've had my moments where I didn't want to nurse either of them ever again, but for the most part it has been okay. I do think it has helped the transition to "big sister" a bit as well....tonight S. gave Z a hug and told her that she loved her....awwwww.

Nancy