This is going to depend entirely on the headphones being used.

If you have a pair of Stax then the difference is going to be pretty apparent, my Grado's also do a very good job at digging out fine details and I noticed a marked difference on some material, most noticeably on piano segments which made each note sound more natural and tight with less ringing which I find fatiguing on other material.

Ultimately I think the difference between the non MQA file and the MQA version is going to depend heavily on the quality of the production and the equipment in use.

I think older recordings are really going to come alive.

T

Lounge: DSP33's, MS200, QNAP (Storage and Core), G68D, HD421
Family Room: DSP5000
Kitchen: F80
Portable: Explorer2