I use HiTech or Nulon full syn in mine . According to trans tech full syn is good for 60k, where as DXIII is more like 20-25k. Given they run fairly hot because of the small converter I think full syn is the go. Plenty of blokes running DX3 without issue though. I pay to have mine serviced and syn from the tech is only a tad more than DXIII as he buys drums of it but rarely uses DXIII these days unless requested.
Someone on here mentioned some problems with Penrite full syn, such as slippage. I decided to not try it just in case.
I changed my VE 2008 Anniversity Auto oil and Filter yesterday and used Penrite Full Syn Auto oil ATF LV. Yes Full syn oil mixed with other I think , I think Mineral oil. The VE has 158,000 on the clock and I think this is the very first oil change on the Gearbox since coming out of the Holden Factory. The oil still had a orange look at it considering the mileage. Yes there was clues that told me the auto gearbox has never been touched before.
Now the Next Auto Gearbox to do in the next month (other jobs to do first around the house and yard)) or so is my Son Statesman (The OP) because know one knows how long that oil is in that gearbox.
We will buy Dex 3 (castrol) oil 4 ltr container as I did my VR Commodore 3 months ago and that uses DX111 and still have a little left because the VR only uses a little less than 4 ltr.
By the way I re-designed a screw driver to remove that seal on the filter tunnel, Long, just wide enough, very smooth and collapses it without leaving a gouge mark in the circle where the new seal goes in.