An important part of PCI compliance is protecting your virtual environment, and a hardware firewall is a part of that protection. Like all technology hardware, firewalls have a usable life and cannot be supported indefinitely. It’s a good idea to know when your hardware is reaching the end of support.
WatchGuard Hardware End of Life Dates:
https://www.watchguard.com/wgrd-trust-center/end-of-life-policySonicWall Hardware End of Life Dates: