have had this VND for a little over a month now and I can say it is a very useful bit of kit to have in the bag. Natural light shooters will appreciate being able to cut down light to shoot at wider apertures, and strobists will like that plus the ability to stop down ambient light to match strobe lighting without having to go into HSS. I haven't tested it with video, as I primarily shoot stills, but for the film shooter on the go, this would be very useful. Quality seems to be there, its a metal filter, and the glass elements seem well constructed. I was able to count hairs on heads, so the effect on a cameras resolving power seems to be little to none, which is good. Autofocus on the a9 and the 70-200 GM seemed to be fine It comes with a little plastic case, which fit nicely into the bag without taking up too much space. The adjustment of the filter is obviously easier without the lens hood, even though the 70-200 GM has a built in access for adjusting VND's I did a quick backyard test with my son to illustrate the exposure versatility of VND and it does indeed provide 9 stops of exposure adjustment. Having that flexibility is useful for many different types and styles of video and photography. I provided a composited image showing the 10 frames I shot. I also included an image where I used the filter to allow me to slow down the shutter, and turn the water circling around a boat into something with a more dreamy, or painterly effect. The last shot is using the reflective blue tint on the filter element to reflect the clouds over the image of the boat to create a double exposure look, the VND allowed me to only cut some of the light and still create a reflection, opposed to using a cell phone, or a mirror which are totally opaque. to do this, i took the VND off the lens and angled it in front with my hand until I got the composition i wanted. Few tips for people new to using filters or VND's, don't over tighten the filter onto the lens. These things are made to be lowprofile and have fine threads, so go easy. There is a tick mark on the non-rotating part of the VND. Make sure you adjust the rotating marks on the filter off the position of the non-rotating tick mark. There are no clicks, or hard stops, just a fluid movement, so keep an eye on your adjustments if your moving around a lot. lighting conditions can change. Lastly, you shouldn't be using this indoors, unless you are trying to hss lights or purposefully cut lighting. VND's of all kinds typically don't have a neutral setting, so they are always cutting down some amount of light. Typically, indoors you want to be gathering as much light as your can. So when you come indoors, pop the filter back in the bag. Overall, I would recommend this VND filter. There are much higher priced VNDs out there, but if you're here, then your probably not looking at the $200+ VNDs on the market. This is a good filter and will get you great results, plus the blue tint on the glass element looks really cool. I have really enjoyed shooting with the VND, hope you like yours