With processor power levels exceeding 200 Watts and nearly 25% of the overall processor junction-to-ambient thermal resistance budget consumed at the second-level thermal interface (TIM2), the use of an all-metal interfacial thermal path is highly desirable . Phase Change Metallic Alloys (PCMAs) offer superior thermal performance due to their high thermal conductivities and low contact resistance resulting from their excellent surface wetting. Also, reworkability and ease of handling make PCMAs attractive in a high volume setting. The current work utilizes packaged Thermal Test Vehicles (TTVs) for thermal performance characterization and an In-situ Test Vehicle (ITV) platform for reliability testing. Comparative thermal performance between a PCMA and organic thermal interface products will be presented. Additionally, reliability data from PCMA samples subject to various environmental stress conditions will be discussed.