The gold standard for colicky, gassy babies — the internal vent system genuinely reduces air intake, and you can remove it once feeding settles.
If your baby is gassy, refluxy, or a fussy eater, this is the first bottle to try — the two-piece internal vent is the most proven anti-colic system on the market, and the reason it's a NICU staple. The tradeoff is more parts to wash, but the vent pops out once feeding matures, so the bottle grows with you. For most families, this is the safe, boring, correct answer.