In Duke Ball, the seam remain intact for almost 50 overs and it has prominent stitching where as in kookaburra, it hardly last for 20 overs and in SG ball the seam remain upright and intact for even 80 overs but it does not swing after 10 overs, as it loses its shine very quickly. But SG ball has got other advantage and that is reverse swing. SG ball is good for reverse swing after 40 overs or so. SG balls drift well in the air and hence it is another advantage for the bowlers.
The SG ball sounds as though it is great for spin bowlers and why India favor it. They are the only country that use it to my knowledge unless Bangladesh favor it as well.