Came across this cause i was curious if anyone uses RFTs. Wow, so many miss-information and bad opinions here... I'll throw my 2c...
I have 2013 BMW 528i with runflats (aka SSR or MOE) and i have nothing against them. Love piece of mind.
I've never put regular tires but car rides better than any other i've owned and quiet too. Its all about the design and those Germans got it right
Yes, RFTs are heavier due to thick sidewall design but my car still gets 25mpg so its not noticeable on ICE car and i don't care lol
I drove on flat few times and it did its job well as intended till i get to place to fix it. I've also used plugs few times just as any other tire.
Inner wear?? its not due to RFTs, all BMW/mercedeses and some others use heavy negative camber for handling in the back that wears any tire...
Price?? i buy used RFTs (~7-9/32nds) mostly and they run same price as regular, i'm on 3rd set already, each set lasted 50k btw (interpolated for used).
Potholes?? i have 140k+ and all my wheels are still straight. If you're hitting potholes that damage your wheels with RFT then i'm pretty sure you'll just cut right through regular tire driving like that lol
Getting a flat is rare but its a gamble... I've had no flats for like 8 years then got 2 in few months and one was on my Jeeps LT245/75R16 tire...
Now as for Tesla, i don't blame them for not including spare for many reasons as y'all mentioned.
I'm definitely will throw plug kit and compressor for cheap insurance. Maybe donut spare for long trips...
Regarding slime, not sure what kind is teslas but the ones in stores are seriously frowned upon by tire shops, I've had multiple times shops refusing to service a tire that was filled with Fix-o-flat... so i'd be cautious.
Also, i believe RFTs need to have a small lip on inside of the rim to keep it in place when it has no air so don't think you can just put them on a regular rims...
Tire shops however have no issues mounting/dismounting runflats, at least in my experience.