I had my daughter's Subaru Omega in today...down half a litre so I topped it up with the Vantage behind the seat. It's been over a year and not even a 1000km, the oil looks like I changed it yesterday. Maybe I should do those rocker cover gaskets soon, it's using more than a litre per 1000km standing still. I've been doing blotter tests for over a year now (rip the lid off the filter box), and my conclusion is the A3/B4 oils can really be pushed on oci, it has to be into the totally unbelieveable kms and dates before it looks nasty. Other oils are toast when A3/B4 looks like new. So the Nulon went onto the '94 Laser with the B6 (MX-5) engine, and it's getting 15,000km this time, which means 20,000km before I get hold of it.