I think the 180 degree mirror is a good idea. But...

I have had past experience regarding two sets of mirrors; and it has almost gotten me killed (once). On my past 2011 Victory Vision; I had mounted an extra set of auxiliary mirrors on the clutch and front brake perches; since the Vic's built in mirrors were hard to adjust to see immediately behind you. Now I was able to use the auxiliary mirrors to see behind me; and if I looked at my Vic's built in mirrors; I could see farther out to the sides of me.

Problem was; I was always focusing more on the auxiliary mirrors, and it was visually hard to always check the Vic's mirrors as well. I almost creamed into a car during a highway on ramp maneuver, even after doing a head check; because as I was accelerating, I was focused more on the auxiliary mirrors, and that car; though visible in the Vic's mirrors came out of nowhere from behind me.

I got rid of the auxiliary mirrors after that close brush with death.