The first thing that struck me was the build quality of this lens. Immediately it felt so tight in my hand. The focus ring and aperture are excellent. I like the click-free manual controls because I can get everything right. The focus is sharp. At f1.7, the depth of field is incredibly shallow, which is great for portrait shots with beautiful bokeh. At f4, the depth of field is sharp enough to easily follow moving subjects in video. I will benefit a lot from this lens and I have a feeling it will last a very, very long time. Highly recommended.