Just to put things into perspective a bit .
This American company that does this..
"You can go into any mass retailer (Wal-Mart, Meijer, AutoZone, etc.) and buy a 5W/30 (or any other grade) that will perform well in your engine. One of the best-kept secrets of the oil industry is that these store brands are actually the same, quality oils that are produced by the major oil companies. The only difference between these products and the major company brands is the name on the container and the price. Don’t believe us? Try running your own experiment: do a sample on Oil A after a known number of miles, then do a sample on Oil B and compare the wear levels. You may see a little fluctuation, but it’s very rare for one oil to make a significant difference in an engine’s wear patterns."
Another source .
"Oil Specifications All modern oils are manufactured to meet certain standardised European/US or vehicle manufacturers specifications, you'll see them listed on the bottles. For example ACEA C3 or VW: 504.00 / 507.00. If a cheaper, non-branded oil carries a VW: 504.00 / 507.00 spec on the bottle then that means it is 100% suitable for use in any car that requires a VW: 504.00 / 507.00 spec. The same goes for a more expensive, branded oil which carries the VW: 504.00 / 507.00 spec. It also is 100% suitable for use in any car that requires that spec. But no more and no less. To achieve a VW: 504.00 / 507.00 spec an oil must be made up of a predetermined set of ingredients (additives) and it is the same set of ingredients regardless of the brand or price point. With both oils your warranty will be intact and your engine will not know the difference between the two."
So armed with this , I do this .
8 years later and the vulnerable narrow PD camshaft lobes are still present on a high mileage engine .