I had good luck with the Playtex drop ins. But I wanted to tell you that what your nipple looks like on the outside is nothing like what it looks like while in the baby's mouth. My nipples are very small, and I wondered about this too. But one time when my son let go suddenly, I saw it before it had a chance to shrink back to normal, and I was amazed at how large it was. I never would have thought it could look like the nipples on bottles or pacifiers, since mine are very very small. But they do somehow. So I would not worry too much about that. Definitely it gives you a good starting place, but you might have better luck with a different brand than the ones you are looking at, so don't discount them. I liked that the Playtex Dropins had the BPA free liners too. I did not like the Avent, they seemed to choke my son. I also introduced a bottle at 4 weeks, I would not wait too long if you will be back at work at 8 weeks. My pediatrician said 6 weeks, but I had several friends who had problems waiting that long,so I just gave it a shot at 4. Good luck, and congratulations!