This is by no means a remarkable product but it feels pretty solid, attaches nicely to the camera and extends shooting time. It obviously does make the camera more bulky and heavy than it already is but the extension in battery life was important to me, and I'm sure to a lot of users. Being able to change the batteries while in use so that the spent ones can be recharged is a great feature (hot swapping). Glad Black Magic made one for the 6k pro. I have three batteries but believe that five may be necessary for the kind of work that I do.