Delivery of samples was unbelievably fast and the build quality seems good. However, the parts are labeled with an arrow indicating the UP direction, and it seems to be pointing the wrong way (the rigid locking doesn't stay rigid unless the gas springs are mounted in the opposite orientation). The low-force 50N gas springs also stick somewhat when left in one position for a few days, but it only takes a small push or pull to get them moving again. Overall, I'm satisfied with the quality and impressed with the responsive customer service and near-zero lead time for my small order of sample parts.