I also "vote for" the method where you use the Media Creation Tool to download the ISO file (create media for another machine option, or something like that) then use Rufus to create the bootable USB drive.
It's not that you can't have the Media Creation Tool create the bootable USB, but I'm one of those people who've had the process fail at this stage, twice over time, and you then have to start all over again from scratch, and if you're on DSL service like I am that means a full download of the ISO file all over again.
I prefer the slight extra bit of inconvenience in having to create the USB myself. Once you've got the ISO you've got the ISO, and you can create as many bootable USB drives using it as you like.
I see no advantage of having separate bootable USB drives by machine under Windows 10. You can use the same bootable media to do a repair or reinstall on any machine that has had Windows 10 installed and activated on it at any point in its lifetime. The installer even figures out which Edition (Home, Pro, etc.) you had and will reinstall that Edition [unless you choose to enter the product key (activation key) for an upgraded Edition, which you can do, you just skip that step if you're doing a straight reinstall].
Brian AKA Bri the Tech Guy (website in my user profile) - Windows 10 Home, 64-Bit, Version 1803, Build 17134
Memory is a crazy woman that hoards rags and throws away food.
~ Austin O'Malley