I came into babywearing with my second child, I knew I needed a carrier that I felt was secure for her so I could be hands-free to be able to run after my 2 year old! My back has been thrown out a few times also so I needed one that was extremely comfortable as well. I came across the Moby Wrap and haven’t used anything else since. I did borrow some from the lending library of ‘Carry the Children’ but the slings put too much pressure on one side of my body and the mei tai was hard for me to feel really secure having her in.
The best thing to do is to know what you are looking for when checking out carriers. Borrow some from friends or from ‘Carry the Children’. There are varying price ranges too, one to fit every budget.