Just used my spare tire for the first time. Had to air it up to 60psi, *and* retrieve the security lug bolt adapter from garage at home. (Luckily only 3 miles away from where parked when I noticed one of the rear wheels had lost all air pressure). As a side note, the standard Porsche super-lightweight tire changing jack worked great!
The spare is not really great to drive on, but did get the job done for the <15 mile trip to get the leaking full-size tire fixed.
I also discovered through this that not even one of the optional, super-wide 18" rear Porsche tires could even fit in the rear *or* the front trunk even with nothing else being in them - therefore, carrying the full size rear tire in the passenger seat was necessary! (Good thing Porsche included a tire bag in the tool kit to help keep the leather interior clean.)
In summary, while checking the spare tire air pressure, don't forget to also check for the security lug bolt bit if your car has those!
And if you happen to have a passenger with you while encountering a problem with an optional wide rear tire, you might not be able to take everything with after mounting the space-saver spare tire.