What oil for boosted motors

my machine shop guy swears by brad penn. he told me to always run their 20w50

i browsed around a bit, and i found this article that confirms (different kind of engine, but they actually tested and found that the brad penn 20w50 was great, and switching to a different oil actually caused engine damage)

[ame]http://store.forcedperformance.net/merchant2/graphics/news/Forced%20Performance%20Recommendations%20for%20Motor%20Oil.pdf[/ame]