Bar end mirrors provide the best view. It's simple physics, they farther out they are the better the angle and the more you can see. Naopleons are the best I've tried that match the look of the bike. CRGs are smaller and fold back when hit but look too modern to match the bike IMO. There are plenty of others, most inexpensive ones shake too much to be useful.
If you want to see how they work without spending too much try the Third Eye Bar End or Myrricle bicycle mirrors. Very inexpensive and they both work well if you want to try one but not spend much. The Third Eye's worked so well that's what I kept on my Ducati. The nice part was if one got broken I just needed to spend $15 for a new one
The only hassle I have is that the bike is wide for parking, but many mirrors can fold in to mitigate that.
Scott