Beware of mirror curvature. Lever-mount oval mirror 92568 has a rather flat surface. Rectangular Halcyon-typo 200033/200034 bar-end seem to be just right. The round bar-end is also a Halcyon type but I have no idea of its curvature. The curve on the stock C5 lever mount ones is just about right but the mirrors are in the wrong place (and wobble), I see myself or the grass verges. The pretty Ironhorse
http://ironhorsespares.co.uk/ bar-end is rather flat again. Personally I prefer a single large mirror with a wide field of view, 200034 shows me both sides of the road behind me.
These bar-end mirrors /can/ be fitted outside the bar-end weights but they do act as anti-vibration weights themselves, the weight is not required (they are heavier than the aluminium CGT ones). I have 200034 on the right and a weight on the left. UK legislation allows for stupidity, a mirror is not required to be fitted. Certainly in the 50s and 60s, bikes were not supplied with mirrors. Leon's parents appear to be on a bike with no mirrors

I'm old enough to have ridden legally without a helmet.
Swivelling my head - my jaws are apparently too wide to get a full face lid to fit properly, I find them painful. So I use an open face. I do however have a semi that has good side vision although it is tight on the cheeks. My favourite open lid is an HJC with a sun peak and an internal drop-down visor. If I have to ride in the rain, an open Spada with a bubble visor protects the face; I wear glasses so goggles are out. I also like to hear, and hence dislike lids with sound deadening; you can hear hazards as well as see them.