I honestly could not tell the difference between the glass in these mirrors and the glass in the OEM ones. We'll see when I finally get a chance to ride the bike again. It was tempting last week but the snow on the ground caused me to decide against it. What exactly is flat glass?

 

During the MSF course, my instructor told me the glass on our OEM mirrors are curved, so you can see more area and more of your blind spot. Flat glass is strictly flat, and doesn't show as much.

I think that's what they were telling me. Let me know if I'm wrong. But I heard flat glass is hard to see with.

 

^ Right. Our mirrors are just slightly convex and display more.

 

I ordered mine and got an email that they shipped Saturday. I'm looking forward to getting them.
As for the flat vs. curved mirrors, you should always be looking over your shoulder before changing lanes and such anyway, you never want to fully rely on mirrors when riding. Just my $.02.