I wouldn't use this comparison to settle the prime vs. zoom debate. Fuji's 35mm f/1.4 is one of the oldest lenses on the system, and optically it's not the sharpest, especially in the corners. If you want a razor sharp ~50mm equivalent prime, check out the new 33mm f/1.4 that's getting good reviews.
The technical advantages of primes are better image quality (~95% of the time), a wider max aperture like you pointed out, and that they're typically smaller and lighter than zooms. I also agree with
>>4018791 when you're learning composition. Primes force you to compose for the focal length you're shooting at, as opposed to zooming in or out to fit all the elements into your shot from wherever you're standing. Even if your subject is the same relative size in both shots, there's a huge difference between a shot at 18mm crop and one at 55mm crop in how they look and feel.
That's not to say zooms are useless, though. They're much less expensive than a set of equivalent primes, and you won't have to change lenses nearly as much with zooms. When I take my camera hiking, I like leaving a zoom on as opposed to constantly swapping primes and having to clean dust out of my sensor.
>>4018789Lenses are often sharper stopped down from their maximum aperture. So, for example, while a 50mm f/1.4 lens may be less sharp than a 50mm f/2 lens with both at their widest, the 50mm f/1.4 will typically be sharper with both at f/2. A fair comparison in the OP image would show both the kit and prime lens at the same aperture. Usually around f/8 because most lenses are at their sharpest there.
