Porsche offers two versions of spare wheel/tire for my '14S. Standard brake: 970.362.050.00 @ $673.24 msrp. Ceramic brake: 970.362.070.00 @ $1,271.65 msrp.

As you probably know Porsche, Audi and VW share, with some exceptions, the same wheel bolt pattern - 5x130. I bought a new spare from eBay that fit a VW Toureg. Cost was about $100. It fit my 14S with no issues. I returned it to seller for a refund. I did not like it at all.

This contraption is marketed as a "compact spare". Basically, it is a wheel tire with a tightly-folded sidewall. It is not ready to use, like the typical mini-spare found in Asian cars. You must inflate the tire to at least 36 psi to unfold the sidewall. The wheel/tire contains a 50-55 mph speed restriction, just like the mini-spares. It weighs well over 50 lbs.

Incidentally, I recently had a good experience with a light weight oem mini-spare on my heavy Hyundai Equus. Circumstances required me to use it for almost 450 continuous highway miles. No issues whatsoever, and I could see virtually no tread wear. I did inflate the mini to 80psi and drove no faster than 50 mph. I can't find a mini-spare with a 5x130 bolt pattern.

Now when traveling I carry a tire-plug kit. I have successfully used these on motorcycles. It is much easier to use with the tire dismounted. So, I carry a cheap scissor jack and lug wrench. Incidentally, I have had but one automobile flat tire on the road in the last 30+years. It was a comparatively slow leak allowing me to limp to a tire shop.

 

Just curious, what didn't you like about it? I'm thinking if the Panamera is reacting/accelerating unusual or in an odd way with the spare tire, the traction control might be conflicting with the tire size with the spare intended for the Toureg...not unless they're all the same tire size.

 

Kirkman, Thanks for your ebay suggestion to my spare tire situation. I also have a 2014 911 Turbo S Cab. I have had 3 flats in 6 years. I'm afraid to go out of town and get stuck if I get a flat and the local dealer does not stock my tires. They don't for my 19 Panamera GTS. I am creating a full size spare for the Pana and carrying it in the rear for out of town trips. I think it is awful that Porsche puts "special" tires on their cars that are not stocked by dealsers!

 

The reasons I did not like the oem spare are: 1. it is too big and heavy, compared to usual Asian mini spares; 2. It requires inflation, and I am both impatient and not confident of the Porsche air pump; and 3. The speed limitation. For the less $$ you can buy a used 18" oem wheel and tire for a spare. It can be kept inflated and ready to use. An 18" wheel will work just fine even though your other wheels are larger - assuming you are using the spare just to motor to a tire store.
I would never ever buy a tire from a Porsche dealer. First, they often do not have them in stock. Second, they will charge you more than any other place on the planet. When I really need a tire while traveling I call Discount Tire. They are a huge chain, and can tell me just what is in stock and where. Alternatively, I call TireRack and obtain overnight delivery.
As for these "special" tires with a Porsche "n number", I don't think they are really all that special - maybe they might make a difference if you are Autobahning at 120MPH plus for tens of miles. Check your manual - Porsche just "recommends" n-rated tires, and they never say "why". For normal USA driving a speed rated tire from Michelin, Continental, andPirelli will do just fine.

 

For instant temporary mobility I will be switching to runflat tires, if we keep our Panamera that long. I have not found a runflat for the rear 20" tire size though.

Discount Tire, aka America's Tire, also sells a very good road hazard warranty. Be wary of similarly named stores...