I received all three of these (because I asked for them) when pregnant with DS:
Baby Bjorn Active - Asked for this before I'd researched all the alternatives. DH uses it frequently around the house and for walks, and I've found myself putting it on occasionally as a quick and easy alternative to the Moby. Also, DS is less smashed up against me in the BB, which is a consideration because I am battling thrush, and my breasts are quite sensitive sometimes.
Maya Wrap Lightly Padded Ring Sling - Unfortunately we haven't used this much. DS just doesn't seem to like the sling as much as an upright carrier. He tends to fuss, and I don't find it as comfortable as the Moby.
Moby Wrap - I love, love, love my Moby and use this most of any of these.
Then after he was born, I purchased a cool looking Hotsling, thinking that he might like that better than the more cavernous Maya Ring Sling - unfortunately, he doesn't! The Maya seems too big, and the Hotsling seems too small. Maybe I need to try harder... I've sort of given up on them both.
Next.... I'd like to get a Meitai I think, and/ or an Ergo!