There is no central organization that ranks window manufacturers or window construction quality. There are also various agencies that keep tabs on how the glass in the window performs. One is the Insulating Glass Certification Council, which tests the durability of glass that manufacturers use. If a window dealer has unrated windows, you are not getting the best grade of insulated glass. Another organization is the National Fenestration Council, which seeks to provide accurate information on measuring and comparing window energy performances.
Solar heat gain , or the window's ability to resist warming from sunlight.
Visible light transmittance , or how much light passes through the glass. No, they are not. You would pay for labor. Look for warranties on both material and labor, including coming to your house to make the repair, rather than you taking the window to them. Whatever window you choose to install, be sure the manufacturing company has been in business awhile.