Q: wanna change the mileage on my 2014 Mercedes E350, does x300m support?

Answer from obd2tool.com:

Both OBDSTAR mileage programmer –X300M and OBOMASTER can support E Series w212, W211, and A207(E-CABRIO)  to do odometer correction

Here we take ODOMASETR for 2014 Mercedes E350 W212 mileage programming  as an example:

Select “Cluster calibration” then “Benz”.

Select “E series”.

Select “W212”.

Select “Mileage Calibration”.

The next process will be as easy as a piece of cake, please just follow the on-screen instruction to do