Significant product testing is required to develop a truly "carrier-grade" free-space optical transceiver. In addition to engineering a system with high availability and an appropriate feature set, it is necessary to ensure reliable operation across a wide range of operating conditions, including temperature extremes, inclement weather (e.g. rain, snow, wind), and vibration. It is also important to guarantee consistent performance between units, in order to enable efficient manufacturing processes and improve the customer experience. This paper describes the engineering confidence and design acceptance testing process and results for Terabeam's next-generation access transceiver. These tests include bench performance testing, thermal and other environmental tests, and performance testing at range.