Thoughts on Neutralaudio X-Drei, wrt BSG QOL

Hi Al, that's a really helpful comparison of the effects of both units.
Since they work on different facets of the signal, what is your hunch as to how they might work in series ie one after the other between pre and pow? And if you feel this might be positive which sequence would you choose?
Thanks for your time, Marc.

Thank you, Al. The X-DREI appears to be subtractive, whereas the QOL may be additive. As a result, I think it may process the signal less than the QOL which on another thread is possibly revealed to be a mid-side processor.
I think that if anomalies such as square waves in the ultra HF range are smoothed to correct sine waves this may reduce unnecessary load on the power amp/speakers and improve 'intelligibility'.
As a result I am tending towards the X-DREI since 2 units in series may be overkill.

So, the X-DREI merits so little discussion (your comments, Al, notwithstanding) as compared to the BSGT QOL which has had a TON of comments.
I'm a little confused as to how 2 units which claim to have such a fundamental improvement to sound quality and sit in the audio chain in the same place ie between pre and pow can have such varying interest levels from A'goners.
Both are obtuse in explaining their effects, and both have had limited reviews (X-DREI in 6moons, QOL in TAS), but X-DREI experience amongst listeners seems to be much rarer than the QOL.
A'goners, please post thoughts or this thread will go the way of the Dodo!
Marc

I guess that I'm commenting on the lack of user comments on A'gon. The X-DREI has had same overall limited coverage as the QOL (1 review each, minimal advertising), both promise substantial improvements over regular signal, but QOL ends up getting momentum of interest and X-DREI...nothing.
Surely all the QOL proponents should also give this unit some consideration. Note, I am not affiliated in any way with product, just getting my head around whether X-DREI or QOL, or indeed neither is way to go.
Will trial device in Summer myself.

There's a really vigorous debate on the dedicated QOL thread. The majority of listeners are positive on sound improvement delivered by the unit, but others are skeptical, and a few have surmised it is a mid-side processor (a process most audiophiles incl. me weren't even aware of). This is backed up a mid-side expert on the Audionervosa forum who claim to replicate it's effects with proprietary studio mastering equipment.
Listeners who like the unit have really taken offense to this possible revelation about the QOL, and I agree most wouldn't have gone for it had this aspect been alluded to.
I've invested in a SpatialComputer Black Hole to help with bass nodes/standing waves, and even though their website is a little uninformative, enough of the principle was explained that I knew I wasn't buying into a 'secret' process.
The point of this thread is to get opinions on the X-DREI which really doesn't seem to have developed anywhere near the same profile as the QOL.
Again their website is obtuse, but enough of their explanation seems to make logical sense as to the purpose of manipulation of unwanted square and triangle waves which undoubtedly contribute to HF hash in the signal emerging from the spkrs.