Review (5/5): Speed booster works.
It works on a Sony a6500. Gives you more speed. Sharp in center. Is it generally as nice as a sigma 1.4 e mount, or 55 mm ziess 1.8, FE, no. Native lenses use camera I Q, on Sony it's important, but for some old zooms, macro lenses, that speed and manual focus let's you get a lot of money worth out of old glass.