I think it varies from baby to baby - I've been recommended TT CTN by a few friends but Emma hated them! If she had them from birth it may have been a different story (I introduced the bottle at about 12 weeks after exclusively BFing). She just couldn't get on with the shape of the teat. I picked up a Dr. Brown's to try and she guzzled her milk no problems, she is easier to burp than when I was BFing her, and has no wind problems.