I think all wireless alarms "suffer" from the same thing, The devices need the batteries changing every year / 2 years / 3 years (various factors depending) The cost of the batteries will never come down, you can not see what is causing a problem, very good equipment is not cheap. I just looked at prices, when you start adding up all the items, it soon becomes costly.
You will be better off with a wired alarm.
Oh, and there is no tech support for it *, as its NOT meant to be a DIY installation.
*Unless you are an SRi