I remember a while back, the biggest competition for fan supremacy on a radiator was between the Noctuas and the Scythe Gentle Typhoon, with both sides being quite strongly argumented over cfm vrs sp vrs rpm. To look at the new 120mm A series, it looks like Noctua took the criticism to heart and combined the GTs blade design style with Noctua performance and ability and got the best of both for a truly superior fan.
In any pump, and a fan is just that ... and air pump, the efficiency of operation is to a great extent tied to the material tolerances. With even small degrees of shaft wobble, that shaft defection extended over the 60mm radius can have the impeller blades hitting the shroud. So by strengthening the shaft / bearing and improving impeller rigidity, allowing the manufacturer can reduce tolerances, the amount of blowby is significantly reduced which should also reduce noise as well increase output.
As for the grainy appearance I have to wonder if that isn't tied to the strength properties of the new material. It's the fibers in fiberglass that are responsible for it's rigidity and strength and these are quite visible before the gel coat is applied. My guess is they are using some type of composite.
Obviously Noctua didn't like being kicked off the throne almost 4 years ago when Phanteks knocked them off the throne. Kudos to Noctua for investing the T E & M (Time, effort and money) for the 5 years it took to seemingly overcome the challenge.
The last published test results I saw had the Phanteks keeping the CPU 6C cooler at the same rpm (1200), the difference dropped to 3C when the Noc was pushed to 1500 rpm.
There's two things however that I think will keep these new fans from being widely adopted.
1. At $30, it's twice the price of the current performance leader and those ar routinely discounted every few weeks on newegg. I tend to wait until they are $10 (for the 140mm) and buy a dozen at a time. On my current rig, (6 case fans, 10 rad fans), that takes the fan bill from $160 to $480.
2. The fugly colors. I thing for Noc the colors are a"badge of honor" thing where users can proudly proclaim that they are wise enough to focus on function rather than "looks". Even for the most ardent nerd however, the idea of having significant aesthetic clashes is at least a minor concern. However, give the preponderance of posts on the board where LEDs are the major decision factor, it would seem that in the form versus function battle, function has gone from sitting in the back seat to the trunk for a large portion of PC builders. For me it was something I was tossing over in my mind when deciding what to use on the then upcoming build, fortunately, the test results made it an easy decision. If the performance of these fans lives uo to their design tolerances, won't be so easy next time.
The only led color that doesn't change the overall colors of the Noctua fans is bright white. Throw in any other color and that tan surround changes drastically. So the only time, honestly, that anyone with led lit case should have any issues with color is when the pc is off. Really?