Hi.
Honestly, it all depends on what kind of driving you do. Whether you go fully synthetic, synthetic blend, or mineral/conventional, I'm confident that all the oils made by the supermajors and well-known names are up to the task.
As long as you go with the correct viscosity, and whatever is recommended in your owner's manual, then that's a good place to start with and stick with.
In my opinion, it is not as productive as it seems to ask people for their opinion on which oils to choose because each one has their own preference. No offense of course!
I suggest that you look at the various oil analysis online for your generation Porsche and see if you can make some trends between them. I'm pretty sure the oils will do the job. The discrepancies and variations between analysis are due to the environment, the driving style, and the condition of the car's internal components.
Have fun! Nice car. I really like the Boxster.