A follow up: my evaluation is there is not much one can take from the second paper on a more thorough (though brief) review. It looked the most promising at first glance. It contains many results and covers a broad area. The approach was careful, logical and interesting. However, neither sample sizes nor statistical results are given. This is generally a tell-tale sign statistical power was inadequate (indeed, some of the confidence intervals suggest as much). I hasten to add this was a forum note, to be fair. This was likely to have been a report of work still in its early stages that will or did occupy some years, or evolved in other directions.
The other paper I looked at briefly was the fourth. There were some dubious statistics and language in the survey of previous studies, forgivable perhaps because these studies date to a time when negligible effects could be reported as "highly significant"*. Looking into the country-of-origin effect on perceived quality, it was reported "the country-of-origin factor proved to be highly significant" (p.17). I read on to find the partial eta-2 - full credit to the authors for reporting this - to be 0.08. That is, about 8% of the variation in consumers' perception could be 'explained' by this factor. Actually, slightly less as there was a brand-country interaction as well. OTOH, their structural equation model - the piece of work developed by the authors and right in their area of expertise - could well be pretty good.
The lesson from just these two of the four papers - this is not a big sample - seems two-fold. First, there is a relevant literature out there. This needs to be pulled together, plausible hypotheses developed and then tested in the audiophile setting before scientifically valid statements can be made. Science progresses by experimental test; deduction alone is not sufficient.
Second, if effect sizes are all about as small as suggested by these two papers, many factors are necessarily involved. A complex explanatory model is the almost certain outcome. This may not be a bad thing. In particular, it allows for non-linear effects, especially if there is feedback in the system. By non-linear, I mean large differences from small changes and vice versa.
As I am rather overdue on three large writing projects I had hoped to finish before Christmas - and I foolishly undertook a review for head-fi! - I won't look into the other links nor go any further into this for now. Interesting material for next year I think.
*note: the word pairing "highly significant" is unscientific and no statistician allows it. A result is either significant or not, just as a light switch is either on or not (I'm assuming a dimmer is not in circuit). We do not append, nor do we need, this kind of qualifier. A switch is not "highly on" for example.