If you could find a willing M60 owner in your area, maybe they'd be kind enough to let you bring your own speakers(towers) to the audition as well. If not, you would need to make sure you use demo material that you know inside out. It's the subtleties that separate the better speakers imo.

BTW, when I bought my Axioms, I intended them to be used about 80% for HT much like you, but I find myself listening to and buying a lot of music again...50/50 music/HT.

Half of communication is listening. You can't listen with your mouth.