just popping on for a very quick hello and saw a specific mention of slings from juwesm - I had a didymos (wrap sling - non-stretchy) with ds - was fab but going with an ellaroo for this one at least when it's wee as the only bad point of it is that it's quite warm.
I'd always go with a wrap sling over a baby bjorn cause of the length of time you can wear them without getting a sore back - but as someone else said, maybe its not bad if you get it properly fitted.
But wrap slings take a little practice but then are pretty quick to put on, hold the baby in the best position for their hips etc and can carry them for hours without back ache.
as far as I can tell, stretchy wraps are great while the baby is wee but they grow too heavy for them much sooner than the non-stretchy ones.
The didymos is expensive online £75+ usually - but i got for £50 at a baby show - definitely one of my best purchases.
others are cheaper but not always as good.
and thats my sermon over.