Well, my first question was “why use this when the 14-24 f2.8 is the best wide angle zoom in the world?”. Not to mention, this is an older design with a bit of chromatic aberration in the edges. And at f2.8 the 14-24 may resolve a bit better in the corners, despite the fact this is a prime.

But the 14mm does have some advantages. It’s much smaller and easier to carry around. And, unlike the zoom, it doesn’t suffer focus shift so if you’re shooting at f3.5 or f4 this may be a better choice. And while the 14-24 is a bit better in the corners, they are otherwise very comparable: sharp, distortion free lenses that provide and exceptionally wide angle view.