What about the new ergo performance. It's made of cool mesh so will suit a hotter climate although you will be using an infant insert from newborn so that could be hotter. It's also more slimline and better fitting and will have all the known benefits and comforts of the ergo - I have a sport here in QLD and that would be my preference above an original ergo. Or I'm thinking if the prospect of wearing a ssc with an insert in summe is too much maybe a ring sling made of a light fabric like the the breeze baby..will double up and take you in the water too. I used a ring sling for four months then Ergo up till now, but regardless of what you have..its gonna be hot! Breastfeeding on the go with an insert will be quite hard but you should be able to do it better in a ring sling as you can adjust easily back and forth and with correct positioning you should have a nice close feel so you can go about your chasing a toddler feeling safe enough
Close carrier will be way too hot for QLD. Actually, anything that doesn't come with built in air-con is too hot for bl***dy QLD (grumble, grumble, stinking hot today). Ergos can be difficult to feed in - SSCs in general can be trickier to feed in as there's less manoeuvrability with the heavier padded waist. And having used synthetic mesh carriers - they are not as cool as natural fibres in high humidity, even if they are breathable and thinner - they trap moist air and feel disgusting in the tropics.
I've been using a Storchenwiege 1/2 buckle quite a bit with my newborn - it's made from wrap fabric so it's soft and light and quite cool, yet really supportive (I wore my nearly three year old in it in the latter stages of my pregnancy with DD). It's height and width adjustable for smaller / larger babies, and the sleep hood rolls up the zips away, which shortens the body for newborns and acts as a head/neck support. The waist is unpadded so it's easy to feed in. I'd recommend it purely on the basis of it ticking all of the boxes of what you need it to do. A good ring sling is also handy to have - I use my ring slings frequently but wouldn't use one as my only carrier. Linen ring slings are great in the heat.
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