I never knew how good headphones could sound until I tried Stax earspeakers. They are truly in a differnt class than anything else I have ever heard. The spatial experience is different, of course, but very involving in it's own way to me. The speed, resolution, and immediacy are 'better' than any speakers I have yet heard. In fact, if there is a track where I can't make out some of the lyrics during normal listening, I usually can with the Stax. I started out witha humble SRD4/SR40 system and gradually moved up to SRX Mk3 earspeakers and a SRM-T1S tube driver as my budget increased.
To me it's not either/or; it's horses for courses. @tony1954 put it very well.