Other posters have summed it up well, but for my part: - I have had run-flats on three BMW vehicles. I had one flat, and it was a straightforward repair. It isn't so much a matter of not driving on it, as not driving on it while deflated. The tire repairer needs to be sure that the tire structure hasn't been compromised by being overheated due to excessive flexing.
- Early run-flats were harsher riding; this latest generation seems pretty good to me
- If you want to carry a spare, do so. On the E70, there is room for one as long as you didn't order the 3rd row seat.
- If you want to carry an inflator and sealant kit, like the M-series, do so; you can buy them from BMW dealers or many tire shops
- The real reason for spec'ing them is to allow a controlled stop from speed, without losing control. They are better in this respect than non run-flat tires.
- If you did have reduced side-wall flex (which I am not convinced of), you would get better mileage, not worse.
- You can call BMW Roadside Assistance any time you like if you aren't mobile, whether you have run-flat tires or not. Ask them to send a flatdeck so that you don't destroy your run-flat tire.
- If you have dedicated winter tires at home, which isn't such a bad idea, you will always have spare tires available if a replacement isn't in stock. I do agree that until they are more common, finding a replacement run flat tire can be a challenge.
To me, whether a vehicle has run flat tires or not is a non-issue. There are pros and cons of run flat tires, but to me it isn't enough to influence a purchase decision on a new vehicle. Also, it isn't as if the move to run flat tires is just a BMW initiative.
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2007 X3 3.0si, 6 MT, Premium, White
Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
2002 325xi 5 MT, Steel Grey
2004 Z4 3.0 Premium, Sport, SMG, Maldives Blue
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