[Ticket Question] Texecom Kit 3 32 Zone Self-Contained Wireless Kit

[Secware]

Hi I need to replace my current wired alarm system.. I have a mains wired alarm with wired connections. I have a couple of PIR's that are wired, which I see no reason to replace as the cables are hidden. I would like to add additional pirs wireless. I can see execom Kit 3 32 Zone Self-Contained Wireless Kit which looks like it can take 4 wired zones. So I could install this on my current set-up and add wirless pir's to additional rooms. I have a couple of questions. How is the alarm disabled. Is it on the control panel? I see it comes with 2xPremier Elite SmartKey. What exactly is this? Can this disable the alarm without having to put in a code? I have 2 children which I would not want them to have a smartkey. Just simply put in the alarm code. Is the alarm easy to implement on my current set-up?
Thanks