They are solidly built and do the job. Somehow I initially managed to loosen a clamp a bit - I set the clamp force too much and it didn't open wide enough to be used. A quick message to the support team (super responsive!) who told me to unscrew the adjustment screw all the way and open the clamp all the way. Turning the screw at this point required needle nose pliers which required more force than I thought the screw would hold but it worked. Now everything is in order.