With DS1 we had a Moby wrap, Ergo, and Beco Butterfly II which we will use for DS2. I picked up a Gemini a few weeks ago because it was a smoking good deal and I've heard great things about using them with newborns. I'm looking into the TaylorMade Water Sling Melanie posted about a few months ago. I'm just wondering if there is a certain age period that slings are really good for? I'd like to use it for showers and next summer in the pool. We are going to WDW in April when DS2 is about 4 months and I was thinking it might be nice to use the sling as it seems like it would be cooler than our other carriers. I didn't know if they are more uncomfortable once baby reaches a certain weight.