Richard (Devon),
I had the standard mirrors, but changed them late last year to the John Taylor versions - they are excellent.
I could not see out of the nearside mirror no matter what I tried.
John Taylor's version allows the mirror to fully rotate....
I'll second that on John's mirrors - excellent. Available from Phoenix Designs, the website is morganhoods.com
I've never looked back! Or what I mean is I can now look back
(I know, I know, I use that every time a thread comes up on how rubbish mirrors are)