[Andycam]

Wondering if the community could help me out here as neither my future dealer nor BMW Sweden seems able to provide an answer.

Is it interchangeable to use non-runflat tires on a car factory delivered with runflats?

The reason I'm asking what is perhaps a stupid question is that when I ordered my F32 in 2015 runflats were the only option from factory. I had heard a lot of negatives about runflats over the years and was a bit concerned in terms of ride quality, performance etc. My sales rep then said that runflat technology had evolved and those caveats were gone and that the car was also designed specifically for the characteristics of runflats - shocks etc were all designed with the harder tires in mind. Therefore, I was strongly advised to stick to runflats summer and winter tires as mounting non-runflats would alter the feel and behavior of the car to the point of affecting safety.

I'm now about to get a used 2019 M850i that's delivered on 20" runflats. I'm not a massive fan of big rims, I prefer a more compliant ride and if given the option I would have preferred 19". First-world problems... So I'm thinking of getting non-runflats for my winter wheels and for the summer 20"s when the current ones are put out to pasture. If I look at the BMW online configurator it seems that for all rims on a new M850i there are two cost-neutral choices - runflats or normal tires. Would that affect anything in the manufacturing process or is it now perfectly fine to swap back and forth between runflats and normal ones (provided you don't mix of course) without drawbacks?

And do you know if the serious uneven and massive tire wear issues reported on the 8 in other threads are related to normal or RFTs?