Logically a ghost ring rear sight should be much easier to access and use than a notch and blade. The sights on the M-1917 were superior in speed of use and accuracy to those on the M-1903. When the Army developed the M-1 Garand and M-1 Carbine, the aperture was used and it was made very large. When Remington simplified the 03 into the 03-A3, the rear sight was moved to the rear and made a aperture... a very large one. Now some complain about having a problem using such a sight. Almost always it is because they are trying to look at the rear sight, font sight and target. They soon learn to look through the rear sight, focus on the front sight and aim at the target. It is a extremely effective sighting system.
I know that the notch and blade is traditional on handguns. But, a good quality adjustable ghost ring rear sight combined with a properly set up front sight would be a very fast sight for range or field use.
It's about like using a laser sight. It is not traditional. However it's utility is undeniable, especially in low/no light conditions when getting hits is essential.