well, the vert mounts ARE oem, but just came on verts. Vert mounts are stronger, and perhaps a little stiffer. I believe the hatch/notch mounts were of a two piece design, while the vert mounts are one piece.
Now, the difference between oem vert or hatch/notch belts vs the autozone mounts are night and day, junk vs something that will last a while, that's why I suggested if you can't find oem vert mounts, then go with energy suspension poly eurothane or an aftermarket mount. Only want to do this once right?