With having more conf/video calls the K520 keyboard caused noise issues while taking notes on calls. While I can mute myself, it's not optimal if you're one of the primary participants that trying to take notes and be fluid.
After searching on "quiet or silent keyboards" I ordered the MK470 and MK235 keyboard mouse combo sets. While not technically "silent" the MK470 is the quieter keyboard between the two and much quieter than the original keyboard + mouse combo. in the attached video I tried to be as consistent and realistic when illustrating the sounds of the keys and mouse clicks. All of this is objective and i'm simply trying to give a helpful review for others who may have the same needs.
In an additional effort to reduce keystroke noise I also purchased an inexpensive wireless headset to move the mic further away from the keyboard vs. being located on my earbud cord. Switching to the headset itself could possibly reduce the keyboard noise heard on a call, but that said, I have co-workers who use the K520 during meetings with their webcam + mics that are mounted on the top of their monitor and the keystroke noise is quite intense. Again, many factors to consider in mic quality, etc.
Overall i like the MK470. It is a condensed full keyboard that types like a laptop keyboard. The keys are quieter than most and I've confirmed the ability to type during meetings w/out being disruptive. The only short-term challenge for me is getting used to the location of the forward delete button which is differnt than a full-sized extended keyboard layout. I will be recommending this keyboard to my co-workers who also need to type during calls. Good luck to you in our new norm and I hope this was helpful.