Yes in Security updates I guess they are the quickest after Google devices,this update was released by Asus on 1st November but it was just for Beta testers,today it was released for all
Asus even provided Volte feature to Zenfone 2 Laser(both variants having Snapdragon),I am also expecting an update for Volte but problem is that Zenfone 2 has Intel processors so chances of getting Volte update seems to be 50 50 but still hopeful that Asus won't forget their last year's flagship :shy :shy