I agree with Somar.. If RRL has been selling high end denim, then he should definitely know the differences between the unbranded/N&F and high end denim. However, it seems that RRL does not, which is interesting.
I'm not a big denim head, but I do own a pair of Uniqlo, N&F Deep Indigos, and Helmut Lang straight leg raws. And let me tell you, the difference in denim quality and construction between N&F and HL is astounding. The biggest difference is in the hardware and construction. Denim-wise, they both are cool in their own way: the HLs are slubbier and rougher, the N&Fs are hairier and softer to touch. HLs are also much faster-fading.
The higher end you go, the more character denim has I believe. Just check out pics of Samurai or PBJ (esp the 007s), they have depth. The intense labor that goes into high end Japanese denim is also not a facade: I've spoken to Jay from Blue Owl about this. I'm sure you guys agree he would have a significant amount of knowledge on this matter. The labor is in the way the denim is dyed, and the care that goes into making each pair of jeans. It most definitely is not a 15 minute matter.
Unbranded is cheaper as they manufacture overseas, I think it was Macau. N&F has also been able to somewhat keep prices lower as Brandon manufactures in his family's factory. One last thing, denim even within Japan is of varying quality. Kaihara denim is different from Okinawa etc.