They do have modified breaks and slight ecu modifications. But nothing that gives a great difference at least that what happens with bmw and Volvo. Bmw also come with extra wiring looms and inverters from the factory where as most other manufactures don't and they have to be converted by a third party. Bmw also sell them heavily discounted. Did a 4wd fleet evaluation last year and bmw could supply x3's for £15000 each converted and liveried so very cheap!