I was looking forward to using the sling as our little boy loves being carried. I cannot emphasize enough how disappointed I was. I persevered for 2 weeks but in the end decided that this item is absolute rubbish. Our usually very calm baby would cry after about 5 mins in the sling every single time we used it.
I watched their enclosed instructions DVD and proceeded to put baby in the sling. As he likes to look around I first tried the "laying-in-the-sling" position. The problem with this is that the sling forces the baby to curve around your body meaning that if the baby wishes to face forward the baby has to turn its torso around leaving the legs facing one way and the baby's top half facing the other. This was very uncomfortable for the baby and, as the baby's spine is twisted, I would imagine quite bad for it's development. It also meant that I constantly had baby's knees pushed into my stomach (I'm fairly fit and do not have a pot belly!) which was also uncomfortable for me. Contrary to their carefully posed DVD shots the top part of the sling remained slack and it constantly felt as though baby would roll out if I bent forward even slightly.
Having tried this position for about a week without success I then tried the "front-to-front" position which the DVD states can be used from 4 months, which our boy is. This is where things really went wrong. This second position requires that the baby "slouches" into the sling with its spine curved to force the backside down into a seated position. Our baby prefers to keep his back fairly straight and does not like to slouch, this resulted in our little boy literally sliding out of the bottom of the sling on 2 occasions! Luckily both times I was holding him otherwise he could have been badly injured. After the second incident the sling was immediately consigned to the rubbish.
For us at best this sling was totally useless, at worst dangerous. In either case it was a complete waste of money.