What struck me, even before seeing the filter, was the attention to detail with regards to the packaging. Starting with a beautifully crafted box, a handy protective leatherette case in which the filter came wrapped in a small plastic protective pouch. The filter is made of quality materials: a metal frame with two hard rubber grips: one grip to secure the filter to your lens and a second rubber grip to select the perfect neutral density for your lighting situation: not too loose, not too tight. The addition of a large tab on the ring makes it easy for your fingers to quickly rotate the filter and avoid twisting the filter right off the lens. But most importantly, this product is constructed with high quality optical glass. The results? After multiple tests shooting photos and videos, there were no signs of vignetting in the corners and no visible image distortion. And no “X” pattern throughout the entire density range. Wow, this company goes all out to show how serious they are about making quality products. I’m very happy with my purchase!
EDIT: After thorough testing outdoors in bright daylight, I did notice some slight vignetting at the “darkest” setting. Seeing as I shoot mostly landscapes, this is really not an issue for me.