For what it is worth I had VX SS Series 1 from 30,000 to 110,000 ks (my son's got it now) It rattled and still does compared to my new 6.0L.
The rattle didn't worry me so long as the oil comsumption was ok. It used 1 litre every 10,000 and did so for as long as I had it. The test for Holden...