The End User Advisory Group (EUAG) was created by LF Networking to share views, challenges, and best practices between user organizations; highlighting new areas of opportunity for the developer community. This white paper is a companion to the White Paper: NFV Testing and Automation and takes a deeper dive into how the EUAG came to its conclusions and recommendations. It provides the supporting research and evaluation methods that were distilled into the recommendations made in the white paper. It starts with a discussion of the evaluation criteria used to apply to the findings, followed by an analysis of the existing testing capabilities currently used in the industry and why it is unable to support the new testing requirements imposed by the NFV environments. The final section surveys the testing projects and resources available in the standards and open source communities to date.