I bought these bottles as I wanted BPA free and also something that may help in reducing the possibility of colic/gasiness in my infant.
For the last 3, we have dealt with a very gassy (and screaming) infant all while using these bottles. We are now on our 3rd formula and she the gas has been greatly reduced; however this was due to the formula not the bottles. As others have mentioned, there are more parts to clean & put together than usual (which I was fine with if they were good bottles that also helped with gas issues). Unfortunately, they have issues with nipple collapse and leaks. In addition, the newborn flow of the nipple in this set seems to be too fast for my newborn as she choked every time she ate. I thought this was "normal" until I bought another slow flow rate bottle and found she does not choke with a different bottle/nipple.
Note on the gas: We did try all the other basic remedies to reduce gas (i.e.: holding baby upright while feeding, holding her upright for 20 minutes after feeding, burping, feeding in a calm environment, etc)
I first found these bottles for my nephew who had feeding problems. These were the only bottles that helped with his reflux, so when I found out I was expecting I couldn't wait to grab these up. I am going to nurse and the shape and feel of the nipple really helps cutting out any nipple confusion. I was very disapointed however when I had opened them and they weren't the glass bottles. I am sure it stated on the site that they weren't and the important thing is that they are BPA free BUT was a little sad none the less.
After a whole year of trial and error, I finally got these bottles, oh what a joy! No air like in others, no bubbles, and very easy to clean. I have used them for the past 4 years with both of my kids, the only thing that you would need to change is the rubber insert ( not sure what it's called) and the nipple, just try to be gentle with these when washing. If you see there's a leak, it means it's time to change these. 5 stars...
These bottles are great, my little guy never had any problem with colic, but to be fair I haven't tried any other bottles. The vents are a little bit of a pain to clean, but it's not really a big deal for us. I had a problem with little tears in the vents after a few months, but customer service was exceptional and took care of the problem with no hassles.
I have been very happy with these bottles so far. They do not leak at all. Also, my baby is breastfed and has no problem with any nipple confusion with these bottles. They also feel sturdy and well-made in your hand.