Esoteric SA-10 vs Opus 21

If you're patient, GNSC modded Opus 21's pop up used here on A'gon for about the price of a new one, or less. The unmodded Opus is excellent, the modded version is stellar. Sorry, I'm not familiar with Esoteric.

I heard an Opus 21 against another Esoteric at a show, possiblyt the X03. The latter was more detailed, but the Opus clearly one out. It was musical, fast, with more than enough detail. Everyone else in the room at the show, prteferred the Opus too. I have a GNSC modded Opus 21 and it ain't going anywhere

Anyone with any experience of the unmodded Opus 21 vs. the GNSC modded version?? Also, GNSC has two levels of mods-any thoughts of the standard mod (I believe it is $950) vs. the reference mod ($2000)??

I have the GNSC reference mods and did compare with someone who bought over his unmodded player for an afternoon. Very clear difference, we both agreed on, particularly, a tighter deeper base output. In general though a bit more transparent, better detail, but particularly, base improvement. This seems to agree with the general view of the weakness of the Opus 21, if it has one, the base and how the mods improve it.