The thing is that the engineering was already made on those airbrushes when Iwata started to license manufacture them. It is an Olympos design. And truthfully, the Olympos needles and nozzles are even better performing than the Iwata components.
What is that "independent" source saying, really? That he finds out that Iwata uses better materials in their $200 HP-B or their $400 CM-B than Paasche uses in their $100 VLJ? On a side note, I believe that article has been discussed quite intensely on some of the airbrush forums, and not only in mild tones....
Try to put things in perspective. I'm not saying that Iwata make lousy airbrushes. I say that they make very good airbrushes, but to shout out "everything else is JUNK" is not only infantile, it is also wrong. There are lots of good airbrushes out there. Many of them have positive sides and negative sides compared to Iwata. In my opinion the Olymposes are better made than the Iwatas, especially the microns, where it is almost disappointing to use the Iwatas after using the Olympus's for a while. I have several of both brands, and must say that the Iwatas lack the precise feel and smoothness of the Olympos made Microns. I would put even the Olympos SP-series above the Iwata made Microns. Even some of their HP-series airbrushes feels smoother. Would I recommend Olympos to anyone? No, since they have closed shop, they are for enthusiasts only. Second hand prices are getting ridiculous and spares are harder to find by the day. You can use Iwata spares for most of the models, but they take a hit in performance.
So, what the alternatives? In my honest opinion there are lots of great airbrushes out there. Almost all the japanese made airbrushes are made to the same standards as Iwata (and no, they are not all made in the same factory). The airbrushes from BB Rich, both their own and the rebranded ones like Tamiya and Mr Hobby are very nice, usually comparable with Iwatas HP-series. But if you live outside of Japan, spares are hard to find. But they are not less well engineered. Most of them are based on the same HP-standard airbrush as Iwata. Nothing fancy, but works well.
For people living in the US, Badger is undeniable a good alternative. Not based on performance, but pricing and availability. The newer models like the Patriots and Velocity and Krome seems like good airbrushes. I've never been especially fond of Badger, but that might be because in my part of the world they are about twice as expensive as they are in the US. How many of you think that the Patriot would be worth $180 or the Krome $270? And parts are probably harder to find for Badger than Iwata or H&S. And just as expensive. I would also say that the Badger Sotar is better than the HP-B, though, which it is priced against today.
Paasche seem to have marketed themselves towards the beginner and not so enthusiastic users lately. I have noticed that they seem to have dropped their quality control. Lots of complaints about parts that have shaky tolerances and sometimes raw feel. And at least here, the Talon is competing in the same price-bracket as some of the H&Ss and Iwatas.
Few airbrushes compare well to the microns, but of the non microns, the Paasche AB is definitly a contender when it comes to detailing capability. Another pair of top of the line airbrushes, the Efbe A and B are probably there as well. And both the Paasche AB's and Efbe's I've tried where very high quality. Junk? Definitely not.
And the ever so popular Harder & Steenbeck airbrushes might not be my favorites either, but they do have their positive sides. The Infinity Solo is priced at the same price as the Krome. The Evolution Silverline about the same as the Patriot. Are any of them a lesser airbrush than the Eclipse in engineering? Some of their fans, including a couple of Pro's, judge them to be as good as the Iwata Microns....
Add to this the Iwata Kustom line of airbrushes, that I find to be almost a joke. Engineering? It is marketing all the way. Larger cups, taller triggers, shiny boxes, nothing more. At about an increase cost of 50%, on already high priced airbrushes. And yes, I have tried a couple of them as well. And I seriously doubt that many custom paint artists are using them in anything but promotion. I find them extremely clumsy.