I learned to drive driving trucks and farm and ranch equipment. I started driving a Ford F8 fuel delivery truck when I was 16, and that old beast just had 4" round rear view mirrors. Uncle Sam let me drive duece and a halfs around Germany for 2 1/2 years, I drove snowplows at Lake Tahoe and other parts of Nevada for 3 or 4 years, pulled travel trailers and drove motor homes for 35 years, so I feel I know how to use mirrors. Never had an accident. However, whenever I drive my Mustang in traffic I want just a little more visibility, especially on the passenger side.
Not much you can do with the sports mirrors except put a convex mirror in place of the flat mirror. In this age of technology there are bound to be better solutions.
I agree with Eric, a nice mirror with 3 video displays would be great, but the only one I've seen is the one from vision tech, and it is a little lacking in in size for the center display. So, I'm thinking about one wide electronic mirror with two smaller ones mounted on the sides in a custom bracket or mount. The smaller ones would supplement the sports mirrors with fairly wide angle cameras.
Even though my headliner isn't new, it's in good shape, so I don't want to drill holes in it, either. Maybe a pair of rear view mirror windshield mounts will work. With the variety of shapes and sizes of cameras that are available unobtrusive mounting locations shouldn't be a problem.