Qualitatively, this converter absolutely nothing to worry and he also works properly, the image quality is outstanding, ... but only to my SONY SAL-70400G, and because even with manual focus. I wanted the converter like to use mainly to my mirror lens SAL-500F80 telephoto, so as to obtain a focal length of 1,000 mm, but unfortunately non-existent: The inner lens arrangement of the telephoto makes a touchdown on the converter impossible; This is also in many other Sony SAL-lenses that.
Only after unpacking I could find a list of the few, compatible lenses with the accompanying description. Since these limited possibilities were not mentioned in the product description on Amazon, I had the converter willy-nilly return again: I would not even ordered it, I would have known it. ... And therefore only 3 stars, although the converter would basically deserves 5 stars.