The full windshield entirely covers the front of your side-by-side cab. The complete coverage provides protection against dirt, rock, branches, dust, and other debris flung toward the nose of your machine, and also shields you from oncoming wind, precipitation, and sun glare. Keep in mind dust can swirl in from the sides and the rear of your UTV with a full windshield, though you can mitigate this with a rear windshield or full-cab coverage.
A full windshield is a great choice for many riders, especially those who do a lot of cold-weather off-roading. However, if you plan on going mudding, this may not be the solution for you. All it takes is a single mudhole splash on the windshield, and you can wipe out your view completely.
With some full, fixed windshields, the lack of airflow can leave you and your companions feeling a little warm on nicer days or in warmer climates. However, many models include adjustable vents or strategic openings to help with airflow throughout your machine.