If I lost this sling tomorrow, I would order another one immediately, from day one it really soothed our quite fussy/colicky baby, and we are still using it at age 7 months, both out and about and also to settle him if he's upset/tired.
It offers all the versatility of a wrap sling, but is really easy to use and is pretty foolproof. The ring system is really simple, and takes seconds to put on and get your baby into. You can position the baby in a foetal position, so great for newborns, or upright facing in (again good for sleep, our 7 month old still naps in it if we are out), or facing out when a bit older. Our baby loves being out and about in it, and its also great for getting things done around the house if he doesn't want to be put down.
It comes in two parts, the main sling and an extra wrap, I rarely use the extra wrap, but just tie the tails of the sling around the front to make it secure.