I am with The SEARCH Group and do research and development for our law enforcement courses. One of the topics I have been doing extensive research and development on is the use of WinFE built from a Windows 8.1 Pro install. WinFE is forensically sound and is portable via a USB thumb drive. It supports most portable versions of common forensic utilities, such as FTK Imager Lite. I have also built a version that will boot a Microsoft Surface Pro Tablet for imaging. Please feel free to reach out to me with questions.