Should I take Pro rate to protect the site from attacks and accordingly the acceleration ? How are things there for protection ?
Protects for short.
Alas, to understand how good the service of protection against DDoS, impossible until a serious attack. Therefore, it remains only the option of studying the history of other sites. From cloudflare there are plenty of success stories, and they initially started as anti-DDoS, unlike stackpath\maxCDN.
So I more like cloudflare.
But I agree that the plans stackpath (traffic instead of number of sites) look attractive.