You've come to the right place! David Vaughn's Ultimate Demos blog identifies exactly the type of discs your friend is looking for, down to the time-code second of specific scenes and what those scenes demonstrate. Also, my last two poll questions asked readers to share their picks for the best Blu-rays to demonstrate video and audio; check out the responses here and here.
BTW, if your friend is an audiophile who likes concert videos, have him check out the Blu-rays from AIX Records. The audio recordings are impeccable, and the live performances are captured in gorgeous high def and, in some cases, 3D.
If you have an A/V question, please send it to firstname.lastname@example.org.