I read that there is some that have concerns about retro-fitting their TV with extended range fuel tanks. Let me offer this.
Concerns about water in the fuel in regards to extended range tanks should be filed under " vehicle maintenance".
Anytime you are dealing with diesel fuel, water admiration is part of the package.
Draining the fuel separator ever so often is part of normal operations. This is why there is a warning indicator on dash board, that you never want to see turn on, telling you that water has filled up to a point you must take action.
This is the same thing as "you have X number of restarts" before the DEF gods put you in the ditch.
Every second tank of fuel with an extended range tank my vehicles receive a pint of "diesel" fuel treatment and a short dump of the water seperator and life is good.
My only real issue with the extended range tank is I don't have the range the vehicle does. When I step out I have to stand up and hold on till my legs start working.