I haven't used the Bob Jones so I can't comment. I went with the Microsight after looking through one on a friends rifle. I love it. It has made a tremendous difference. Front sight is now clear and the aiming black doesn't blur into near uselessness. I'd estimate it's worth 15 or so points to me.
I used to have a fuzzy aperture, fuzzy sight blade, and fuzzy target. Makes lining them all up problematic, to say the least. Now at least the sight is sharp and the target is sharpish.