This has come a long way in recent years and I believe it is very accurate these days, but the problem is that its uneconomic. If I did this on my studs, I would have to pay a one off cost of $25000 to do all my ewes the first time, then I would have annual cost of around $38500 to do my yearly progeny, around 1550 or so at $25 a shot. I can go around the farm, tag them with flexitags, recorded in a Pocket PC for cash outlay of a $1000. Anyone who does this DNA parentage is doing realistically as a marketing gimmick, as there is no way you can recoup these costs from farmers who buy rams at present. They may go on about no shepherding, but you gain a lot of good information, ie bad things about your stock doing a lambing beat, ie cull poor mothers, poor milkers etc apart from saving lambs that otherwise may die, you can still cull those you save its just you might make some money from them first!!
These costs have come down a bit, but still bloody high, the SNP chip genomic test unfortunately the accuracy is better but not that much better to justify paying an extra 30000 a year. I hope there will come a time when the returns justify the outlay, but unless all my clients will stump with another $100 a ram immediately, its hard to see the benefits.