I used one with ds and liked it- it was the only way to get him to quiet down and sleep during those colicky periods in the beginning.
In retrospect, I realize that I did not position him correctly. I looked back at a picture of myself, and ds was nearly horizontal. The model pictures on the website show the babies (even little ones) at more of a 45 degree angle. Having him so horizontal made it look like his head was brunting a lot of pressure on the sling which worried me. But the slightly more upright position looks like the bum takes the brunt of it and the head isn't so smushed against the sling.
I did like it better than my hotsling- the sides don't come up as high on the peanut shell, so his face wasn't as smothered/covered, and the material felt more stretchy (but not too stretchy)
I don't know why I didn't try nursing in it- it looks like it would work, although if you feed both sides at one feeding, it may be an issue.
The sling was very easy to slip off with baby inside if they're sleeping, and you can easily remove them once the sling is off you, or simply lay them down with the sling spread out on their underside. I could even place him in the carseat with the sling still on his underside- that was convenient.
I pulled it out again when ds was about a year old and did the hip-carry, which I liked (around 20-23 pounds at the time)
I did the size small- I'm 5'6" and 115. My sister is 5'8" and maybe 120, and she used it fine too. I did buy it in a store though so I could try it before purchasing. the fit can be tightened by folding over one of the pieces that goes over your shoulder, once the baby is in.
