I have heard that VX dosen´t say there is a problems with the chain, but I have a friend who works for a Opel dealership in Denmark.
I asked him if there were a special recall for z28nel z28net, z28neh engines regarding chain problems:
"Yes, 5 year or 150000 KM/93750miles.
Recall of 31-01-12
Vectra C fra 2008-
Faultcode P0016(1B) og P0018(1B) must been stored in the ECU.
Uprated chain from and with engine nr. HN 055 387 (29. sep. 2010)."
I have just written to him about the recall nr. on this. Which makes it easier for you guys to go to your dealers.
But now you know there is a special recall for those engines from Opel.
I be back when I have the nr.
I also have posted this on VXR Online. So there are also aware of it.