Can't rave about them enough. In fact I like them so much I have two

(although lilfatty has one of them at the mo)
PROS:
Like all wraps:
*baby is super secure in there and you are completely hands free. (I like a pouch sling too but never felt like I could really use both hands to do stuff.)
*they are super comfy - the load is spread right across your back so you don't get sore shoulders or feel lopsided
*they are really versatile in terms of the different types of carry you can do
Specific to Moby wraps: they are the perfect stretch - you can pop baby in and out multiple times without having to retie it every time like you would a woven wrap, and it doesn't slacken off too much.
CONS:
*There is a little bit of a learning curve but seriously, once you've done it 4 or 5 times you're sweet.
*In the middle of summer they do tend to get a bit hot esp if you have a dark coloured one. My first Moby was a black one and it's good for matching with clothes

but I got a Pacific one (my favourite colour) as a bit of a middle ground.
*When you're still getting used to using them you really do need to have a quick squizz in a mirror to make sure bubs is positioned correctly which makes them harder to use when out and about - we've got tinted windows on our car which worked for me
*The length of them means if you're going out somewhere in winter you really need to have it pretied on so you don't accidentally drape the end in a puddle.
I actually found it easier to get JJ positioned right in the Moby than in an ordinary pouch sling, it's really easy to keep their spine straight etc.
Go to the Parent & Child Show at the end of October and check them out in person. Disclaimer - I will be there helping model/sell them. I can't say for sure but I suspect there will be show specials

Or, you're in West Auckland, head along to
Slingbabies!