Multi-Mirrors, would like input...

Since I have started using a head and neck device I find that it might be useful to add one of those rear view mirrors that have multiple mirrors running across the top to aid in seeing around the car without having to move the head as much.
My question is what are the draw backs to such a thought? Anyone shed any experience with this?
Thanks!
My question is what are the draw backs to such a thought? Anyone shed any experience with this?
Thanks!