I love that Sigma has a 35mm Lens that's a 1.2 Aperture for this price and the Build Quality is Amazing! All-Metal Build, really Robust, I love the Clicking Aperture Ring but can be switched to a Smooth Ring which is great if you wanna attach a Follow Focus Motor to do some smooth transition without the click. Using this on my Lumix S1H and S5 has been Great and is nice and Sharp for a 1.2 and since it uses the L-Mount, I have the ability to use AFC. The major "drawback" is the size and weight. It's a Heavy Lens and is big, uses a 82mm Filter Size but it doesn't really bother me