OLD days i use to see Cisco ACE used to do, not sure is this still a cisco product, looks like they EoL long time, then i moved to Citrix Netscaler, does a great job.
Firepower has some features but its not 100% WAF.
How can I measure it?
not sure what kind of measures you looking for here?
some information can be found here : (citrix)
https://docs.citrix.com/en-us/citrix-adc/current-release/application-firewall/introduction-to-citrix-web-app-firewall.html