Thanks so much ladies for all your thoughts it seems, in summary, that most of you like the baby bjorn, the mai tai, the kari me wrap slings or the woven type of wrap or the ring slings.
Also some useful comments on the ergo, little life, pouches, hop panda, bushbaby carriers and macpacs.
Baby bjorn
The good: most thought it was comfy, could be used for up to 9 months, that Dads? like it too, that it gives good support across the back and that babies like being able to face outwards when big enough. It is fast to put on and to take off. Can be used in winter with a wind & rain-proof fleece cover. Babies like it as they are always snug
The bad: might not be as supportive as other types of sling when the baby is bigger. Some only used if for 6 months. Needs to be constantly adjusted for parents of different heights. Some said uncomfy for both babies and parents. It gave some dreadful back ache. Not much freedom of movement for you as with the baby is very high up meaning you have to be careful with bending.
Mei tai
The good: makes even bigger babies feel weightless, loved and recommended. The wide straps are comfy and do not dig into shoulders, you don't even feel the weight of baby as it is distributed more evenly, and you can carry on front, back or side from birth to toddler. One MN tried it out on her 3 and a half yr old and even carrying her was surprisingly comfy. Another carries her DS in it every day at some point. Great for putting baby on your back and much easier to do than a wrap as a back carry. They can be used for tiny babies too on your front.
Kari Me wrap sling
The good: the wrap is fab for littlies, he can be upright or cradled and I can spread the fabric wide across my shoulders for loads of support. It also supports my LO right across his back so his weight isn't all on his bum, and in theory you can BF in it. I use it in preference to MIL's expensive gift of a travel system and it's the only failsafe way to get my lad to sleep highly recommended. Baby can also breastfeed whilst in it, Ds loved being in a wrap from tiny as he was a very upright baby and these days just goes on my back instead of my front. As others have said the weight distribution is great in a wrap and they are very supportive for the baby. With the baby on your front in a wrap you can be totally hands free (unlike a baby bjorn type) as they are snuggled in nice and tight and you can also spread the fabric over their heads to keep them supported while they sleep (not as dangerous as it sounds and there is a gap between you and the other edge of the material so plenty of breathing space!) I could bend over and so on while cleaning etc without having to use a hand to support his head. will give you max, freedom Also might be important :-) is that with the kari me you can actually sit on a chair and type away on the pc whilst with an upright carrier this is not very comfortable
The Bad: only negative point is the wrapping will take same time to get used to. I love wraps like chubby and pickie but would go for a woven wrap rather than a stretchy one like the kari me as they last longer IME.
Woven wrap - ellaroo Astrophe, very nice soft fabric once it has been washed a few times. Don't think there is much difference between different types of woven wrap though so let the patterns guide you!
Ring sling is great for tiny babies and really easy to feed in. It is also very easy for dp to 'drive' and now that ds is a hulking great boy of almost 10 months great for sitting him on my hip. Hi, another vote for a ring sling. Easy to use from birth, breastfeed in and allow baby to sleep comfortably.
Thanks for the tips the babywearer for comparisons between different slings including the baby bjorn and for recommending Natural Mothering.