I did some research on Vista windows. They are supposed to be far superior to most windows on the market according to some people. Their warranty is as follows:
"Vista Window Company will assume no responsibility for glass breakage or screen damage what so ever. "
"This warranty covers materials ONLY. Service calls made from the factory into the home will be made at the prevailing rates. "
So.....they don't cover glass breakage for any reason, whether it's an act of God or the act of a neighborhood kids BB gun, and if the window malfunctions you have to pay a service charge.
http://www.vistawindowco.com/warranty.php