I have tried both types. For my first is classic and for my second is anti colic. You can try to change the teat size. FYI I removed that green thing inside and change the teat size 🤣 because it should fit my LO preference.
I’m using avent natural response. Tried the anti colic one but baby doesn’t seem to enjoy it plus it has one more part to wash and assemble. Sticking to natural response.