For a very long time, the top complaint I've had with the Raspberry Pi is limited I/O speed (especially for the main boot volume). Recently, the Raspberry Pi Foundation announced a USB boot beta for the Raspberry Pi 4. Now, flash any USB drive with the latest Raspberry Pi OS, plug it into your Pi (unplugging any microSD card), and you're off to the races! All you need to do now is run sudo apt-get dist-upgrade -y, then reboot, then your firmware should be up to date. September 2020 Update: USB boot is out of beta! Check out this video for simplified instructions.