If you're looking for a baby carrier to use occasionally there are much cheaper products that will suffice but if you want something you will love using so much that you create situations where you can use it then go for the Ergo baby.
It's really easy to put on by yourself once you have the hang of it but make sure you read the safety info as its easy to miss something just using common sense.
My baby is now 3 months old and I've been using this since she was about 5 weeks with the infant insert which is sold separately (adding the expense). At first I just used it round the house so I could keep her close whist doing the washing up or sweeping the floor but I really did love it so much we started going out on daily walks (something I never would have done voluntarily otherwise).
We also used it around the airport and for getting on and off the plane on a recent trip back to see family and it was perfect for keeping her calm as well as freeing up our hands to carry everything else!
The pocket on the front is perfect for a muslin, a nappy and your phone and keys and the little hood helps to protect baby's eyes and head from the sun and rain.
Baby looks very comfy in a more natural crouching position, pretty much as she would be if I was carrying her and the frame is comfortable for both myself (5ft7 with wide hips!) and my husband (who is over 6ft with a more slim build).
She's pretty much grown out of the infant insert now so you wouldn't need to buy one as long as baby weighs more than 5.5kgs. Although they suggest you use it until 4-5 months of age my baby was 5.5kgs at 2 months and it does seem to be a bit tight for her at her current weight of 6kgs.
All in all if you want a carrier you'll love using for long periods frequently, go ahead and splash out on the ergo baby.