My little one was born a preemie and unfortunately just would not latch, so I was given these by someone whose baby was onto the 8 oz. bottles.

Pros:
I can count on one hand the number of times my now almost four month old has had gas. These bottles have really done their job. This is also the only bottle my little one likes. I also like the fact that I was able to get the Preemie flow nipples for the bottle because the 1's were just too fast of a flow for her. I also find that the liquid in the bottle stays warm for quite a while.

Cons:
Unless you buy the options bottles you have to use all the components. Also, because of all the components that come with this bottle compared to others it takes a lot longer to wash and sterilize. The bottles are pricier than others, but buying the packs of three does reduce the price per bottle by a bit. I also don't like that the travel caps do not come with the bottles and the lids to cover the nipples are not sold separately. I have also had some issues with leaking, but found out that if the bottle is warmed without anything on top that it will stop the leaking.

Last Words:
These bottles have worked well for us. Our little one loves them and they have done their job.