When I first purchased my Boxster, the consencious was that Royal Purple was pretty good stuff, in fact my first oil change was to the Royal Purple 5w-40.
I kept on researching oils and once I learned about polyoester based oils I figured these are what I'm going to use. If your interested in POE (group 5) oils look into Red Line, or Motul 300v oils. Since we live relativly close to a Red Line source, Summit Racing, we went with Red Line.
In the end, it's your car, run the oil your confident in.