These bottles are a little more expensive than others ($58 for 6), but you only need to buy them once. They are BPA free, and have the internal venting system, which reduces colic.. this was why I decided to try them. I know a lot of people are weary of buying them because they're glass, and I felt the same way at first.. what if they break and my son gets hurt? But let me tell you.. they are shatter-proof. I know this from experience. I have been using them for at least three months now, and they have all been dropped onto my tiled kitchen floor at least three times each. My fiance even run one of them over with the car.. yes I know, but this is the guy who drove away from the beach with his shoes on the roof! Just joking.. it was my fault for leaving it on the driveway while I put the baby in the car and forgetting about it. But the bottom line is, this bottle was run over by a not-so-light car, and the only part that was damaged was the plastic top, which was molded into the shape of the tire. So you don't have to worry about them breaking if your baby drops them on the floor. These bottles will last forever! The only downside is that they're a little heavy, but you can expect that with all glass bottles.
Definatly worth the money!