Reference recordings need to be on the list. Seems like many use them and as others mentioned I have my go to "in the room" favorites. Plus knowing what is there and whats not again and again, that is say life like accuracy, familiarity, and repeatability listening to different devices.
Yes, added that new list item to my vote fwiw. By 'reference' I really mean a fairly constant selection of tracks I like to use when trying out gear, not any specific authoritative set.
Useful though. A short while back I was quite taken with a pair of JBL K2 that showed up second-hand nearby at a nice price (especially $/kg). They were gorgeous. But they didn't play sub-bass at all really, so no substitute for (say) similarly sized Focal Utopia. Not that I'm going to afford those, but realising the K2 required some significant sub-woofer-age to render my test tracks adequately tempered my enthusiasm. Was that 'good' or not? Maybe I should've bought them anyway. Someone else did.