Hi Dave,
I bought a pair for low power views of constellations and they give a big boost to your vision by adding 1.5 mags without changing the size that much- it’s like having super-eyes.
They are simple Galilean design and there is some astigmatism and the quality falls off noticeably away from the centre but they are fun in a dark location, especially for sweeping the Milky Way and looking at large clusters like Pleiades, Hyades etc,
Martin