Pros: BPA free, my son liked them
Cons: Too many stages of nipples-unfriendly to breastfeeding
My first son was severely tongue tied when he was born. He was unable to latch. We used these bottles (well their non-BPA free predecessor) and he liked them. He was super nipple confused-I don't think these simulate the breast all that much but they went with my pump. He ended up using a nipple shield. He eventually wouldn't take bottles at all but these were great at storing my milk and the company offered to replace all the bottles for the newer BPA free ones when my son was about 6 months old. We left a bottle for him and eventually his younger brother and they'd take maybe an ounce or so. My word of caution is that there are WAY too many different flows of nipples and for the best compatibility with breastfeeding stick with the 1st stage ones.