well, i can only speak for myself but i always had the feeling that a high buffer darkens the sound a bit. there also have been lots of discussion about this and ofcourse people dont always agree, but it seems for some a large buffer size affects sound quality.
You can bounce the same tracks with different buffer sizes and compare them with the nulling test.
Of course, if you use samples, you should bounce them in place (and use the same file for all buffer sizes) to avoid different Round robins.
I did plenty of blind tests with audiophiles and they did several blind tests with me.
My main experience is that Placebo is really a mighty sword.
On several occasions i did the "spot the difference between two tracks" tests with playing the same file twice. It's amazing. Everyone hears differences when hearing the same track thinking those are different ones. There are some typical placebo phrases ("more depth", "more brillance", etc, etc).
Fact is: music consists of tons of information and the while the ear is extremely powerful there are myriads of details to focus on (Just think of a composition for a >120 piece orchestra).
Listening to the same recording twice always results in perceiving different details.
You simply have to be conscious of this.
If you focus on an element, your brain actually does a +3 (or even +6) dB boost. That's the cocktail party effect. So, focussing on the top end in fact enables an EQ in your perception.
However, there are always possibilities that real errors occur.
E.g. a insufficient latency compensation can do real harm. In the past, i had situations where logic did a wrong latency compensation on busses with bypassed plug ins (often, because i tried different reverbs on a bus and just bypassed the alternatives).
And this really resulted in a bad sound.
But in the end, even if there are differences in the different DAWs, you still have the possiblity to interact. (Missing brilliance -> add some brilliance)
But one has to be conscious of the fact that it's something like 99,98% about the qualities of composer/musician/mixer and only a tiny part of the DAW.