The future of the Fujifilm X mount is bright now that Sigma is producing lenses for the popular system. First was the trio of f/1.4 primes and now this f/2.8 standard zoom. This competes with the Fuji 16-55mm f/2.8 and Tamron 17-70mm f/2.8 zooms but offers something unique; a compact size.
This lens is small, compact, and built well. It's a perfect fit on my Fujifilm X-E3 and X-S10. This is an alternative to using prime lenses for me. I typically like to use a 23mm f2 and pair with a 50mm f2 or 16mm 2.8 and pair with a 35mm f2. This give me similar focal lengths and apertures in one package.
Autofocus is quiet and quick. Its very snappy and doesn't hunt. It simply nails anything I've thrown at it. It uses a stepping motor and not a linear one but doesn't matter to me. Its silent and accurate so job well done.
Images are sharp, have good contrast, and colors are accurate from my point of view. F4 seems to be the start of the sweet spot and would happily live there for most things.
Because the autofocus is good its great for video. It's a perfect match for the Fujifilm bodies with in body image stabilization like the Fujifilm X-T4 and X-S10. The true value of the video quality is going to depend on the camera body you use it on but the lens itself is very capable and will perform admirably.