I did get all three choices correct, but even on my home system the differences were close. Focusing on a specific voice or instrument was how I decided on the difference between the tracks. My impression is that the recording quality has usually been a more significant factor for sound quality than the resolution of the file.
Also, one difference that seems more apparent to me when comparing hi-res files vs MP3 files are spatial cues and "air" around voices and instruments. These are more audible to me when listening via speakers and less so via headphones.