It depends on you. I personally have my main cold-storage seeds in encrypted USBs, hidden in different secret locations. One secret location is in my house, another one in my car, another at work, and the last one in my old room in my parents' house. They all look cheap, ordinary USBs, with directories named "My Files" with old useless/random files from work scattered with the encrypted folder nested in another folder with more random files that contains the seeds. The USBs can only be opened in Linux

This is very smart, can you tell me how you setup the USB that it can only be opened in Linux OS? I think this will be very useful for me because many people don't like using Linux OS, for example, in my country you will never see anyone running Linux on their PC, it is always Windows OS.