I have both. I absolutely LOVED my Trekker and didn't think that I would ever like another carrier as much. I used it for baby 3 and 4 exclusively. Then I found the Ergo with baby 5. It is so awesome! I can get the baby on my back by myself and is awesome on the hip and in the front too. I can't say enough good things about this carrier. I do still use my Trekker for some things but the Ergo is my main carrier now!