i have just bought an amby baby hammock to use for our new baby (due feb). we have set it up and tried to put ds (11 months) in it a few times to test it out. he hates it! he just seems too big and mobile for it and doesn't look comfy in there at all.
i think there are others on here who use them for older bubs so hopefully they can give you some help. maybe it's just my ds, but he just doesn't seem to like it at all.