where are all the posts/reviews about Prana, Philharmonic and others?

Those companies that you mention aren't really brands or manufactures. Half of them stuff drivers into Dayton boxes from Parts Express and most if not all of them buy off the shelf woofers and tweeters from Parts Express types of places. 

That doesn't mean that they aren't voiced nicely and the upper lines have nice custom cabinets and finishes. These types of small companies are popular on the audiocircle forums, as they offer excellent value and personal service from the designers. 

Tekton and Zu separated from the pack by doing something different and promoting the hell out of themselves, which includes being at industry events. 

Dennis uses Parts Express cabinets for some of his speakers, and off-the-shelf drivers, but designs his own crossovers, which is what he’s really known for (he’s developed them for many of Salk’s speakers as well) and does offer custom cabinets for those who want to pay the difference.

Dennis offers incredible value, even uncompromising with some of his driver selections. He probably hopes that more people don’t buy his speakers. Why buy a nice kit speaker when you can have something nicer for less?

Salk, Selah, Fritz, etc use very nice quality drivers and they are rightfully proud of this and advertise this on their better offerings.

In contrast, there are other small shops (and even larger) who pretend that their drivers are custom, as they don’t want you to do the math on their driver to cost ratio. These types of shops often times will use higher value drivers and spend money differentiating their product in other ways.