The OP is making it known they are pleased with the info being shared.
If they are introduced to other options and thoughts on their subject under discussion, is this not what was being requested ?
Products travel far across the Globe, Schematic Design, Topology and reliability of selected components is Key, not the Fancy Name attached to a premium priced component.
My experiences of being demo'd Boutique Parts, has shown at the time of addition and following a period of Burn In. The Demo's ended up with my rejection of expensive parts selected, where original very affordable parts were asked to be reinstated into Audio Products I have had built. The rejected parts and any other down the line parts to be trialed are at my expense. With selected parts needing to be very closely matched, it does not take long for Alternatives bought in become a considerable expense, as a result of the non matching parts being discarded.
I have been able to make these decisions as a result of comparisons available to be had, as more than one Prototype has been produced in Parallel as part of the build intent. On a few occasions the EE Designer / Builder was not able to immediately detect what I was struggling to accept as being an improvement, sometimes the project can be too invested in and becomes personal.
Boutique Parts added to a Circuit is strictly a personal preference for the ones that selected to remain to be used. If channel matching is important to an individual, Boutique Parts Selection can become an extremely expensive venture.
There is not a ubiquitous choice for Boutique Parts, the experiencing them in a circuit is critical to learn what they are able to offer, which is not always going to produce what is the end users preference for the end sound.
I have become settled with to date, the notion that the better end of Audio Equipment EE's, are those that have a substantial experience and really do know how to create an interface of Components and Topology for a Circuit that is capable of producing an end sound that discovers many followers.
When it comes to Mechanical Engineering requirements for a Audio Equipment, there are even less at the better end of being an Engineer. Where the individual are ones who have the known how, to select the most attractive of the modern available materials.
Especially Materials that have inherent properties capable to produce and maintain a design that is with extremely tight dimension tolerances, very low coefficient of friction that is required to create the most optimised mechanical interfaces.
Those who really really know why a particular design must be created are getting rarer. Those who promote their being able to produce their version of a particular design are growing in numbers.
I am not too sure if the the end product from the latter skillsets offerings has the critical quality controls in place that gives the X Factor the former skillsets are renowned for being able to produce.