I cannot be specific since I am completely unfamiliar with the products you have linked to.
That being said here are some things that I would look for in testing the adapter: more than one stop loss of speed, loss of acuity (aka fuzziness) overall and/or in the corners, chromatic aberration in high contrast fine detail (branches against sky), vignetting, poor out-of-focus backgrounds (bokeh), colour shifting, no lens hood. Likely this is not an exhaustive list but it's a start... Good luck!
Chris S