Auto dimming mirror install?

I drive at night in an area with a lot of idiots using their high beams so am considering switching the rear view mirror to an auto dimming one. I noticed two companies make them, Gentex and Donnelly. Apparently Gentex makes their mirrors fit directly to GM standard 'wedge' mounts. But since the Aveo isn't exactly a GM make, it might not use the 'wedge'? Anyone know for sure?