I noticed if i waited along time to use a bottle than my son didn't like it for a long time.

evenflo advanced vented

@sweetness208, which bottles did you use?

I did both with both my kids and had no problem either

those lil cheap bottles from walmat evenflo i think

@babygirl10-11, what kind of bottles did you use?

i did both for all 3 of my kids from day 1 never had a problem

It's best not to for at least 3 months