I really like the convenience of this magnetic filter system. You only need to thread on the base ring and magnets do the rest. Makes it less likely to damage the threads of your lens if you don't have to keep putting on and removing a filter on every time you need to use it. I am using this with a 24-105mm full-frame lens and the base ring works with the lens cap and the hood although you probably need to remove the hood to snap on the filter because otherwise your fingers get in the way.
Each of the filters themselves are quite a bit heavier than the screw on K&F versions, probably because they need to make the filter ring out of a magnetic steel instead of aluminum. Whatever the reason, they feel a lot more premium than the regular K&F version.
In terms of performance, its a bit of a mixed bag. I don't have tremendous experience using CPL and ND filters (this is my first set) so I don't know what's considered good performance at a given price range.

Moving on, the CPL filter (photos looking out the window) has similar vignette to the ND filter at 24mm but appears to cut down quite a bit of reflections in my windows. Not much for me to point our here, it seems to do the job.
The set does come with a UV filter but I do not intend to use it unless I am in a rainy/dusty environment where my lens needs a bit more protection so I haven't tested it out yet.
For both the ND and the CPL filter, I did not detect any noticeable decrease in sharpness caused by using the filters.
I think the performance of these filters is acceptable. I am a little disappointed with the vignette but I have heard of much more expensive filters having similar issues so I don't want to be too hard on this set. All in all, for someone like me who does this for fun, I think its a great system to learn the basics until I can justify the move to something more premium.