Right out the box it worked. Connected to both my Sony a7r2 and a6000 with no issues. Brightness was good, indoors at least. Menu fairly straightforward. No battery included so I attached a random battery pack I had laying around via Type-C cable and powered on with no issues.
Buttons on top side a little odd for me but that's a personal preference so won't knock it on this review. For the price, seems like a bargain. Will update if necessary.