I'll start by saying that I wasn't planning to like this lens. My main gripe when this lens was announced was that it wasn't an 11-24mm or a 12-24mm. While I would like Nikon to eventually release a wider lens, I've come around to the belief that they found a great balance in this lens.The lens weighs next to nothing and doesn't take up much space in the bag thanks to its compact design that gets even smaller when you set the zoom to its storage mode (basically retracts the lens completely). Despite this, the actual build feels pretty solid and I can attest that the weathersealing is excellent. The main thing that really makes this lens stand out is the ability to take standard 82mm circular filters. As of this writing, this is the only ultra-wide zoom on the market that boasts both 14mm on the wide end and the ability to use standard circular filters. Tally up these things and it's probably the most practical ultra-wide angle zoom on the market.All of this would mean little without performance and we come to a bit of a mixed bag here. In terms of sharpness, the 14-30mm f/4 S seems to be sharper across the frame at all apertures than the 14-24mm f/2.8G and it makes the 16-35mm f/4G look like a complete joke. The coatings do an excellent job at retaining contrast and mitigating flare. The color rendition is very accurate (images accompanying this review are uploaded with no color correction using the Camera Neutral profile). I haven't found any notable chromatic aberration to speak of either. That brings us to vignette and distortion.You know that saying that "You can't have your cake and eat it, too."? With every lens, there's going to be some sort of trade-off. Generally speaking, high quality, well-corrected optics will result in the trade-off of a large and heavy lens. While this lens is razor sharp and excels in many optical aspects, the compact design of the lens meets its trade-off in the form of significant optical distortion and vignetting. People who use Lightroom probably won't even notice this because Nikon has worked with Adobe to automatically apply a software correction to the RAW file upon import to fix the distortion and vignette (I'd guess that it's about 2 stops at its most extreme on the wide end), but you'll definitely notice both if you're using any other RAW conversion software. So we have a bit of a controversy here. If the distortion and vignette is corrected automatically upon import in the software so you wouldn't even notice it, does it matter?In my opinion, yes, it does. The reason is because any corrections that you're doing in software rather than optically is going to require interpolation of the data on your sensor and it will inevitably lead to SOME loss of quality. The same can be argued about the vignette where locally fixing it leads to less dynamic range able to be captured in those portions of the image. If you have a Z7 like I have, then the loss of quality is likely not noticeable for most purposes, but it's there and it needs to be acknowledged. Having said this, one can argue whether optical distortion or even a strong vignette are necessarily bad things. I know it sounds pretty stupid to say, but unless you're using this lens to shoot architecture, real estate (like I do), or other subjects with really straight lines, you're not really likely to notice even moderate levels of distortion or vignette as real world scenes are complex enough to mask those types of flaws. If you ARE shooting straight lines, then you're either going to have to live with software correction or look elsewhere. For me, the size, weight, and 82mm filter thread still make this lens much more desirable than a larger, better corrected lens. Admittedly, I cheat the system here by having a sensor with far more megapixels than I'm likely to ever actually need.So why am I giving this lens 5 stars despite these flaws? There's a physical reality that you have to deal with for every lens. Because of this, I believe in judging a lens based on what it's intended to be and what the value of the overall package is. In this case, we have a lens that's extremely sharp, has excellent resistance to flare and CA, possesses great color rendition, is light weight, is compact, and can take standard circular filters while reaching 14mm on the wide end. This is an extremely high quality, 5-star package that's unprecedented in its combination of features. Yes there are flaws, but the only way to realistically solve those flaws would be to make the lens bigger, heavier, and likely remove the ability to take those circular filters. In my opinion, that's the realm of Nikon's upcoming 14-24mm f/2.8 S lens, not this one. This is going to be a choice between functionality (this lens) vs. unparalleled optical quality (a much bigger and heavier lens). I can definitely say that Nikon is making the decision a very interesting one by releasing such a good 14-30mm f/4.