Decided to give the Kelper Optik H20mm erect image eyepiece a work out. For testing I used a Skywatcher Skyhawk 114 reflector telescope. The targets were street lights and buildings around 5 miles away.
Designed more for terrestrial use rather than astronomy, the H20mm eyepiece gives an upright image through a newtonian reflector, which give an upside down image. Out of the box, the 20mm eyepiece feels solid and well built. The extra elements of glass add a little weight.
The small aperture eyepiece has no rubber eye cups. Although surprisingly I found the eye relief good enough for spectacles. There is some internal reflection, which may hinder astronomical targets.
The image itself was clearly upright, with left to right orientation correct. In the dusk low light, I could easily make details in the shadows away from street lights. All colours from street and traffic light were bright and clear. In fact much better than expected.
I would recommend for small Newtonian reflectors in the 3 to 4 inch range. This is because they are light enough to be mounted on a sturdy camera tripod.
The eye piece will not accept astronomical filters, but will work with barlows.
Summing up, I would say it was definately better than expected. Not many about, so hard to find