BPA - free & anti-colic bottles

I have been faithfully using NUK bottles since baby Zaccheus's birth as NUK teats are known to prevent nipple confusion in babies. Baby Zach has no problem switching between milk bottles and latching on ever since he started on NUK bottle and teat. If not for the recent hype in BPA free and my concern of colic, I would have continue to use NUK bottles. My first concern is thus BPA Bisphenol-A and polycarbonate which are present in plastic bottles. It has been reported that such chemicals are harmful to human health. My other concern is colic which is usually presnted in bottle-fed babies between 0-5 months. This is due to the gas trapped in the disgestive tract during feeding. Very soon, I will be going back to work and baby Zach will be feeding through bottles during the time when I'm working. Hence, there might be chances that he will might get colic.
With all these concerns, I decided to look for safe alternatives to replace the NUK bottles - bottles that are BPA free and anti-colic. I read the internet forum and knew that Pigeon has BPA free bottles. However, I am not sure about its anti-colic function. Last Friday, I went to Baby Fair at Takashimaya and saw that the Pigeon booth carry BPA-free bottles. I was excited as not alot of places carry Pigeon PES bottle and even that, most places are out of stocks. The salesgirl told me that Pigeon bottles have anti-colic function and thus I decided to get a small size bottle to try out. However, I planned to change the Pigeon teat with a NUK teat instead as I am worried that baby Zach might have nipple confusion. If baby Zach is comfortable with the Pigeon bottles, I will go back to the fair to buy a few more of the bottles to stock up at home.