I can think of a few things about this rig I would do differently. I immediately made some changes to mine. For instance, the bar meant for the phone tends to sag or move when weight is applied, so I used screws with lock washers to make it more solid. I also added a couple cold shoes for lights. I use a bluetooth remote to trigger the camera, so I'd like to see some sort of adaption for that. For now, I used a thin strip of duct tape to attach mine to one of the handles. I will be using mine exclusively for hand-held still images.
I actually haven’t had an opportunity to shoot with it yet, but I can say that it is well made and I’m sure I will enjoy using it in the future.