Pros: easy on and off, comfortable, front back and hip carry, easy to nurse, easy to use if pregnant
Cons: weight is mostly on one shoulder-- as baby gets heavier it began to give me tension headaches
If you are only going to get one carrier (and don't need/ want to do back carries with an under 9 month old) then buy this carrier!
When I was pregnant I bought a boba, was given a moby and the maya wrap. I used the moby for the first few months but occasionally put my baby in the maya. Then I moved on to the boba and bought a mei tai to do back-carries while I cooked and cleaned.
Then one day I picked up the maya sling and I loved it and wondered why I didn't use it more before. We started using it all the time every day.
It's great for nursing. Baby can nurse while you walk (although we stopped doing this at about 19 months because people were beginning to give us dirty looks). It is still great for nursing sitting down-- I told baby that now that she was older she had to wait until we got wherever we were going and I could sit down to nurse her and after about three days of whimpering she accepted this new rule)
It was especially good once my daughter wanted to be more mobile at about 11-12.
it was great because I could pop her in and out with out any hassle. It became my go to carrier-- and unless I am going to spend a long long time walking or hiking it is still what I use.
My daughter is 21 months now and I find that if I wear it for more than about 40 minutes I get a headache from the knots forming in my neck. Today we often use the stroller (didn't use one at all before 18 months because the maya worked so well) if we are going to walk a lot, or the Boba and I make her walk a lot.
We mostly do a hip carry with it; but also do back and front carries and have since she was about 9 months old -- most people say no back carry before 1 year -- but the maya wrap doesn't stretch so I can't figure out why that rule is in place... use your own judgement on that one.
Even now that she is much heavier than she was as a baby, it is still great around the neighborhood. She walks a lot and if she gets tired, cranky, or I am in a hurry, I just pop her in the sling for a while.
One final thought, a friend of mine has a homemade sling that looks nearly identical to the Maya-- she is now 8 months pregnant and is rocking her sling with a 2 year old in it and says it work really well for her. (with the caveat that she probably doesn't walk around in it for more than 30 minutes.)