Lately I have had the opportunity to test several K&F filters and for the price they have, I think the quality is excellent.
Surely there will be filters from other brands that are much better, but the prices will also be in line with that quality and since I am only an occasional amateur and I don't earn my living with photography, I don't see the need to invest in more expensive filters when these from K&F give me such good results.

The UV filter does not appear to cause loss of sharpness or changes in hue. Not that I have made thousands of comparisons between photos with and without filters, but in the basic tests I did when I received them, I was unable to appreciate anything unusual. For now, this filter stays fixed to the lens to protect it from scratches.

The CPL filter performs its function perfectly. It has a very smooth turn to be able to adjust it to the needs of each occasion and it eliminates almost all reflections.

Both filters can be used at the same time, making it very convenient to not have to remove the UV when you want to use the CPL.

The price of the pack seems very good to me if you don't have either of the two filters yet. If you already have one of the two, it will probably be more expensive to buy the other filter separately.