w204 180cdi fuel filter replacement

[sceh]

There seem to be various types I could buy:

With no filter heater
With water capture connection
Without level measurement
The prices vary wildly from 16 euros for a Mann to 60 euros fr Man or Knecht.

So, any hints on which to buy and any hints on changing it (since I don't yet know where it is located on the 2011 model)

thanks