The sound quality of IDAGIO is exactly what I would expect: excellent.
I am so fortunate that I am not cursed with ears good enough to reliably discern between 16/44.1 and any higher resolution. Or perhaps my el-cheapo $10k system just doesn't have the resolving power. Either way, I am perfectly satisfied with 16/44.1 material.
The good thing about "greater than 16/44.1audio files" is that many of these recordings have been re-mastered. In most cases, that same master is used for 16/44.1 playback, so I have the benefit of enjoying the new mastering without having to listen to it at higher resolutions. I have the gear to do so; it's just not worth the trouble.