Sheffield Lab CD's are wonderful recordings--the Sheffield Lab A2TB Test Disc ("My Disc") is a must have. Other sheffield CDs I would recommend for evaluating your system (and also for listening pleasure):
(1) Harry James and His Big Band, "The Kings James Version"--wonderful soundstage/imaging on this recording
(2) Michael Newman, "Classical Guitarist"
(3) James Newton Howard and Friends--High energy rock instrumentals composed for synthesizers, drums and percussion.
(4) the Sheffield Lab Drum record--drum improvisation of remarkable sonic and musical impact.
(5) Prokofiev: Excerpts from Romeo and Juliet--Erich Leinsdorf conducting the LA Philharmonic, an "unusually" fabulous classical recording.
These CD's, together with some of my favorite jazz recordings, are what I use for critical evaluation of a system across a variety of genre.
Good luck, and enjoy!
Rob