Sleep Problems: Moby Wrap

Moby Wrap Baby Carrier

Has anyone out there tried the Moby Wrap or one of the other Moby products? I found some information on it, but want to get any feedback from someone who has used it before I purchase it. I have tried many baby packs (so I can pack my baby around with me when I need my hands free) and none of the ones I have used are kind to my back and shoulders.