I had a non-OEM windshield replaced in a Honda several years ago, and the glass was wavy on both sides. The installers refused to replace the windshield because they said that they couldn't see the defects. I traded the car so I didn't have to live with it for very long, but that experience along with multiple stories from other people convinced me that aftermarket glass is crap and one should NEVER allow it to be installed in their car; I know I never will again.