oktammy,
I don't think it is good the bottle has bubble in the milk. The baby will suck the milk and the bubble - it will give the baby stomach discomfort because they are sucking back the gas. It doesn't make any sense to have bubble in the bottle while the bottle claims to reduce air...how can it reduce air if you see bubble in the milk le? Bubble = air, this is common sense bor...
Also the "we we" sound that you hear is caused by baby sucking milk too hard...meaning the milk drinking process is not smooth or comfortable.
I don't think these are "normal" lor....
Just my personal point of view.
I really don't like baby products which claim what they can do but cannot. It is like cheating.
I like Playtax more.