I'm intrigued as to the components of this composite - I see one source that claims it is a 9 breed composite which doesn't include Angus, Hereford, Friesian or Simmental. We could have a guess the breed make up competition

I'm not sure that I could think of 9 breeds likely to be in there.
The website page http://www.shaverbeef.co.nz/content.php?article.7 contained some surprising reading for me indicating that the more breeds you have in a composite the higher the heterosis. Doesn't that indicate that some of the severely mongrelized cows that are products of a rancher changing breeds every year should have the highest levels of heterosis out there? If that makes a good composite wouldn't you expect the highly mongrelized scrub cow to turn in the best calves every year too :?