BelRay EXP 20/50 4tsemi synthetic is almost as highly ranked as the Royal Purple HPS and is pretty reasonable here in Canada, about 30 GBP for 4 litres.
I have been using Valvoline VR1, which tested well, however the BelRay tested better and costs the same.
These are both detergent oils as are most of those tested.
For those who do not want detergent oil for the reasons mentioned earlier, there are some non-detergent oils that tested well.
Only trouble is, they are not separated out in the listings
Redline Racing oil was one.
Other detergent type Redline oils did not test well, in spite of their expensive price tags.
Extra high zddp also was not found to be a benefit.
One of the Redline oils that failed under low pressure had 2200 ppm Zddp.
It seems somewhere around 1200 is a good number for Zddp.
Interesting note, when Jim Comstock was doing all of this testing and found great results with the low cost BelRay, he called them to find out how the oil was made.
In the discussion, and not knowing Jim was the Accessnorton oil tester, they suggested he have a look at the Accessnorton forum as there was a member there doing very involved and accurate oil testing.
Glen
