Why is it useful?
When planning your route, have you ever had to cut your journey by a few miles so that you can stop to fill up? Not only does the extra fuel give you the freedom to explore longer cross country routes. The larger capacity allows less time grounded at a filling station and more time exploring the skies.
When you upgrade to the Maverick XL tank, you are not only getting the stylish extended range tank, but also a new fuel line assembly.