About the filters (ND 64 + ND1000)
Perfect quality, no color cast. The leather bags are stable and protect the filter plates.
Of course, I didn't want to test scratch resistance, but it should be many times better than with plastic filters.
The sharpness is not affected.
The filters fit very well in the holder.

The holder is stable and can be removed very quickly thanks to the pusher with which it can be removed, which can be helpful if you want to check the focus again, for example.
I also think it's good that it has 2 slots and not 3 and is therefore not so bulky. This could otherwise become a problem with very wide-angle shots.
Big +, because all ring sizes are included and not every ring has to be bought...

Let's get this out of the way first: Halos and lens flare where ruining my shots when I began using this kit. I realized that, depending on the angle of the Sun the incidence rate would differ. After careful observation I realized that light was being reflected through the gaps between the glass and the holder and/or between each piece of glass.

The modification: I bought 100x100 filter gaskets made by Haida and attached them to the K&F filters. This completely eliminated my issues. Because I had to buy a gasket for each of my filters I gave this item one star for value.

Once modified, my results with this kit have been excellent. The more I shoot with it, however, the more I wish for a system that was easier to use when a CPL is needed. I have worked out a system and I am quite content with the results. Notice that even when shot directly into the sun the results are pleasing. The bridge was shot at high noon and no light leakage is evident. No artifacts, halos, etc. The glass is of good quality. Picture quality is good to excellent.

I like K&F products and I do like this kit but it is incomplete without the gaskets. I contacted them regarding this concern have have received no response. I don't hold it against them but, again, would not get this kit unless you were willing to buy the Haida gaskets to stop light leakage.

A clear recommendation for this filter holder!
The selection of adapters supplied is very large and very useful.

Great value. Filters fit snug and don’t let any light around them. Filters come in a quality case.

These filters are an absolute highlight, convincingly good quality, everything fits perfectly, everything is packed in high quality and protected and safely protected for transport in beautiful cases. The first tests are promising, but I currently don't have a suitable motif to test the full strength of the filters, but I'm absolutely confident that excellent and convincing pictures can be taken with them.

I always wanted to have a high quality gradient filter. And I found him. The filter sits firmly in the holder, the filter holder can be easily mounted on the lens. Everything perfect. Very good quality. Everything feels high quality, all metal and the gradient filter, which is glass, is well made. Top

After a long research and many comparisons, I decided on this ND8 gray filter.

The decisive factor for me was the price / performance ratio, which I think fits very well.

The filter is top processed, without a visible color cast and just does exactly what it is supposed to.

It helps to extend the exposure time slightly or, in bright sunshine, makes it possible to take pictures with an open aperture.

a small disclaimer: I'm not an ND1000 filter person, I find their water/cloud smoothing effect mostly unnecessary and overdone, overused and overhyped (and many more overs). having said that every once in a while I need something more than ND64 so I decided to give this KF a shot, especially as it came at 40 EUR with Black Friday discount.

I didn't expect wonders and was prepared for heavy color casts. it turned out to be better than I expected. there is obvious color cast with this filter (photo 1) and to all the claims of "I see no cast" I can only reply: turn the AWB off, please, how can you discuss color casts otherwise, seriously?! but with WB adjustment it corrects (photo 2) very close to original colors without this ND1000 (photo 3). scale of correction: 5000K->7200K and 0->

sharpness for wide angle lens (35mm) is perfectly OK, as expected. I do notice heavier vignetting (both lenses have same degree of lens correction) which I'm not sure how to explain but I personally don't mind some in landscape shots.

Overall, I'm pretty happy. it's an inexpensive alternative to brands already known for heavy blue casts (I love your ND grads, Lee, but your Big Stopper is plain and simply a blue filter, period) and for casual usage you can't really expect more

I’ve been wanting an ND Grad filter for a long time, decided to go for the K&F as all of their other items are great value for money,
I wasn’t disappointed when I tried this,

Packaging: great care
Filter holder: ingenious (belt extractor) Anti-
scratch: excellent
Anti-grease: excellent
Anti-reflection: excellent (designed to be used in full sun)
Gain f / stop 11 (example allows you to lengthen the shutter time from 1 / 125 to 16 seconds)
I am attaching a shot made at 35 mm on FF with k & f Nd2000
f8-30 seconds.
Do I recommend it?
I love it, you do.
Good light