Don't know about the Boxster, but in my Miata it was the same oil in the turret as the tranny. I purchased RedLine for the diff, but that was a different fluid alltogether. 30,000 miles does seem like a lot of miles for a boot.
But again my Boxster only has 12,000 miles so I haven't disected anything yet.
Check the Renntech forum I've seen toolpants posting on their and he seem like
biggest DIY boxster owner here.
yeah the title should read "notchy shifter", my friend who is an ER resident says since cialis came out they have had allot of stiff shifters. Appartnely the only way to fix the "stiff shifter" is to withdraw fluid from the "shifter" just like you would withdraw turret oil!