you are thinking of yourself, not the future.
a good quality hard wired alarm, will last for years and add (v small) value to the property, never needs batteries changing every 6 months (radio ones do/ should)
good quality wired alarm good selling point
radio alarm, good for a laugh
you seem to not /unable to accept the information that is put before you, the fact the radio alarms are crap
as for the line (from the link you provided) "are the only ones that allow your pet(s) to roam freely without setting off a false alarm"
i have never heard so much BULL in all my life,
take for example a cat, it will jump about / onto furniture when you are away,(but not when you are there) so coming into the "sight" of detectors setting them off
why dont you solve your problem in the following manor, buy 1 litre of ice cream, eat it, wash ice cream tub, paint ice cream tub nail tub lid to wall, but "base" onto lid
I have seen it done
this message is sponsored by bt*
(*it isn't really but it does give it more "clout")
and i am being honest about the above, are they?