Swarovskis. Yummy, the difference in clarity when your peepers are looking through optical glass of this calibre, is remarkable.
Its just a heck of a shame, that the top three, Zeiss, Leica and Swarovski, charge far too much money for the average person to enjoy the experience.
I still do not regret blowing in excess of £300 on a small optical viewfinder, as the image quality almost justifies the cost, and i know i will have this little Monocular for life.