Unlike the iPhone, which is subsidized by carriers in exchange for a long term contract, prepaid phones are typically sold for a modest up front cost, and service is paid for month-to-month.
There is no question that the up-front ticket price is the most important consideration today in China, not the cost per kilometer over the life of the vehicle.
Vendor lock-in may be unavoidable at this point, but what companies need to do is understand up-front what the exit strategy will be, and build those costs into the initial cost analysis.