Originally Posted by RedRockin

Many threads on this already here, xbimmers.com and bimmerfest.com use the search and type in "spare tire". I'd help you but search results links sometimes don't work when posted in threads.

In brief, some do switch to non-RFs but usually for reasons like they prefer the ride/quality/performance. With 3rd row, not many spare stow options - other than the obvious. Many are using fill-a-flat type options. BMW makes a "mobility kit" with filler and compressor that uses latex. The BMW kit can be pricey (around $180) and the same basic kit (without the fancier case and gloves) can be purchased as the Conti Comfort Kit from Tirerack.com (another latex product) for about $80. Latex has been reported to damage TPMS. Slime makes two different types which both use a water soluble filler which is supposed to wash out without damage to TPMS (but TPMS will likely not function properly until washed out). the Slime "Safety" kits use a one step process where the filler gets pumped in with the air while their other kits are 2 step (remove valve core, put in filler, replace valve core and pump in air). here are some links:
Amazon.com: Slime Powerspair - 48 Piece Kit Tire Repair Kit: Automotive

Amazon.com: Slime 70005 Safety Spair Flat Tire Repair System: Automotive

Amazon.com: Slime 50051 Safety Spair Roadside Emergency Essential Kit: Automotive
From Slime web site:

Tire Rack : Continental
From the web site:

Amazon.com: BMW Genuine Mobility Kit - Tire Repair Kit: Automotive