OK -- my Medela gave out. It wasn't getting any suction. So I figured I'd try the Avent duo because I like the idea of the soft inserts.
The edge of the soft inserts caused severe nipple soreness. Then without the inserts, I was still getting sore. I finally figured out that the shields were too small. Now I'm bleeding and I can't even nurse or pump because it is so VERY sore.
According to AVENT customer service, they don't even make a larger breastshield. I'm out $350 and they basically told me tough noogies. The local BRU was very accomodating and I may be able to exchange it for a Medela and buy the larger shields.
My advice to anyone looking at pumps -- unless you are SURE you won't need a larger shield, get a Medela. I am of average weight; I am not large breasted; and I don't have large nipples. I was also able to use a regular shield when I exclusively pumped with my son 2 years ago. Your body changes.