RE: Can I use different type of nipples on my Avent bottles?
Avent has a great marketing ploy...Avent bottles only take Avent nipples. :) If you do wanna pursue trying differnt nipples, Playtex makes a sampler set so you can buy one bottle and try variou nipples.
FWIW, DD is BF and we gave her an Avent bottle starting at 2 weeks without issue. But magically, at about 2.5 months, she just didn't want it. I did not want to pursue the different nipples avenue and eventually DD just took it. I really think babies will take any bottle once they're hungry enough.