This seems to be a very hit and miss area. My local dealer confirms that Run Flats will not affect the warranty, are ok to fit on Standard rims, but wont fit them.
Esure.com confirmed with underwriters on two seperate days that it was OK to use non RFT's once when I phoned to ask, and again when I called back to say I had them fitted.
Esure.com confirmed with underwriters on two seperate days that it was OK to use non RFT's once when I phoned to ask, and again when I called back to say I had them fitted.