You drive home on your RUN flat

I also have a spare in the garage, dont really know what the gripes are about the run flats, I dont have any issues with mine.

btw- what is the "bmw assist" marketing bs?
I have only used it once, but it works just fine.

My original comment was if non-run flats were installed and there wasn't a spare in the car, but in the garage.

Don't know what the BMW Assist marketing bs is. I would like to know too.

My comments about the BMW marketing BS was in regards to what BMW sales persons often say when they are trying to sell you the idea of a car equipped with RFT without a spare.
Whenever the question is posed to them about the eventuality of a flat- their typical response is "BMW assist" to have the vehicle towed to the shop. This typically takes at best an hour for them to get there and which often implies that you will be quite delayed.

Don't get me wrong, I like the idea of RFT but only from a safety point of view. The RFT allows me to manuerver the vehicle to a safe area to change the errant tyre. I can imagine going on a road trip and having a flat tyre without a spare, how far can you go without a spare before you ruin the tyre and be forced to stop. And to be quite frank not every city has a BMW dealership to get a new tyre.

BMW assist will provide other services if a dealer is not near...and the runflats are rated for 100 miles.

That depends on the weight of the vehicle.

i've been getting some rattles from the back, it might be the tailgate.

I have the OEM 20" on my 4.8 and will be driving 3K fully loaded. If I had a flat would it be better to use that little spare?

Either way, how long might I drive? There will be many part of the trip where the nearest BMW dealer will be at least 150 miles away.

For safety's sake, use the spare. Run-flats have their limitations, and the more weight, speed and distance you subject a RF without air in it, the greater the change of catastophic failure!!

Run-Flats are great for the initial loss of air, but not so great to drive on after.

At reasonable speeds, you should be able to go several hundred miles on your spare tire. If you take it very easy, you could even make it home from your trip on the spare. The RFTs are rarely in stock.

Thanks, but as a novice I am confused. The spare is a different size than the 20" OEMS (2008 4.8) so I would have thought that would present it own set of problems.

The spare is the same circumfrence as the regular tires, so it will not damage your differential. It is much narrower with less contact patch, so you should avoid high speed or spirted driving. But again, the spare will handle and be much safer to drive on than a deflated RFT.