I have the GSO 15mm Superviews
in my WO bino, and they are there 95% of the time. I tried GSO 15mm Plossls and couldnt always get images to merge,
no such problem with the Superviews. Also gave the GSO 25mm Plossls a shot, but saw no advantage over the supplied WO 20mm oculars,(fields of view fairly similar but the WO were to me better in that the extra magnification
was an advantage.