Thank you again everybody. This is all really useful and especially having seen the photos I am convinced that (as usual) Mrs613 was right and our trim days are behind us!
Presumably a lot of customers settle for the trim because they either don't know that something better exists or they don't want the extra cost (time) of mitring? Perhaps both?
I think I get the principle, so I will experiment with some scraps and see how it goes, but you have all given me a lot of confidence now, to know that it's possible and how good it can look.
All the best guys and thanks again
K613