I found C + E I’d need all the mirrors most of the time,I find less need for the wide angle view in rigid but watching your trailer wheels on some turns in artic can be a fair way off to one side. Having said that I had a bad patch on the reversing manoeuvre, which I put down to using the wide angle view to see my steering position of osf wheel then trying to carry on with that mirror to align to the b and c cones, when I went back to the main view mirror was much easier as the perspective is less skewed.