I second the Ergo. The straps aren't narrow at all - in fact, they are quite wide, and very well padded.

I can't feel it at all on my shoulders when I carry the kids in it, cos like Trish said, its all around your waist.

If your DH is tall though (difficult to tell from pics) then you'd be better going for the Ergo Sport though - cos thats made for taller people (ie my DH can't fit into my normal ergo so I have to sell it on ebay or something and buy the sport - he wants to carry around his little princess!)