I bought a Baby Bjorn Active, which is supposedly good to use from newborns onwards, presuming they are over 3.5kg - DD was under 2.5, so it was weeks before we could use it. So when she was a newborn we bought a ring sling, which she liked and was really comfortable until she got to about 3.5kg, then it was only good for short walks or around the house. We are now using the Baby Bjorn Active and I think it is brilliant. I can walk around for literally hours without DD getting heavy or hurting my back or anything.