Non-Oversampling (NOS) vs,

You cannot compare different DACs such as one that is NOS and another that does OS.  In my DAC, the NOS setting is way more musical, I built it that was for my own preference.  The OS has its benefits also on my DAC.  The soundstage gets wider, you hear more detail and more clarity.  Nothing to me that makes me want to give up the musical (emotional) sound that the NOS provides.  But people who have purchased my DAC prefer more details.  Kid of like the tube vs. SS camps.  As someone else mentioned above, always tradeoffs in this hobby.

Happy Listening.  

You just need to listen to Redbook on a "good" R2R dac/cdp that you switch from NOS to OS while listening on the fly, like you can with the Holo Spring.
NOS is far more enjoyable, it has more body to the mids, it seems to extend both the bass and the highs, you can definitely hear the decay (harmonic structure) of piano and cymbals down into silence far better than you can with OS. OS seems to chop it off, a little like Class-D amps also do for me.

Cheers George

@soix2 - DAC is a DHT (direct heated triode) tube DAC with separate power supply RR2R board, V-Caps & Caddock + Shinkoh resistors.

goole: vujadeaudio

the Denafrips Pontus allows you to change from NOS to OS at the touch of a button.
I do change the setting occasionally but always find myself going back to NOS whether the music is served or streamed.