My collection is about 70% 44.1k, 15% 96k, 5% up to 192k, 10% DSD (mainly DSD128, up to DSD256).
The benefits of M Scaler are consistent over the various resolutions IME, bringing more flow, naturalness and palpability to the DAVE.
Apart from special cases, e.g. recordings from the 50's and 60's in 16/44 format, where the HMS really brings this music to a new life, I find the effect of the HMS more related to the
type of music / recording
techniques than to the
format.
For example, my Pink Floyd collection in 16/44 benefits from the HMS less than, say, The Trinity Session in 24/192.
What I mean is that when tone, timbre, spatial cues are especially relevant for the enjoyment of the musical message (as with most acoustic unamplified music recorded live) the improvements of the HMS are most apparent to my ears, even starting from very high res or even DSD material.
And the same applies to minimalistic recordings (one or very few mikes, minimal processing chain), where the M Scaler gives me that goosebumps illusion of pristine replay of the real event which I strive for in this crazy hifi hobby