helix ultra has better HTHS property - meaning its oil film is very resistant to tearing while in bearings. Not many oils meet this - the handful of oils meeting this criteria include mobil1 0W40 - having a too high viscosity index is not a figure to be judged alone (search bobistheoilguy forums to learn abt them)
and any oil having a lower cost of operation with correct required performance standard is always welcome.
e.g. - in my old mercedes' differential I used cheapo 80W90 GL5 gear oil, no fancy stuff, Why did I do this? it was filled with it at the factory too, and the performance requirement is of that too.
another point to think of - all these boutique oil co. like amsoil, redline, LM etc. boast all their products - yet none are offered as factory filled on any manufacturer.
