You're saying that, but £kitchen socket + £reconnection + £carrying on with existing monitoring = £?
Vs. takeover and digiair = £?
Could be drastically different over the long run.
If ADT had offered a GPRS solution, I wouldn't have taken any issue with that, at all. I am NOT anti ADT (or any national)
OP, the reasons the wireless extender is no good (and this may differ to how you understood it / how it was explained) is..
1. It may not support the kinds of data the alarm transmits due to very tight bandwidth / clipping
2. It may or may not provide 50V when the 'telephone' (alarm modem) is perceived to be 'on hook'.
3. If the above is wrong, in that case it would almost certainly still provide 50V even when there is no outside line, so the alarm would not know the line had been cut / failed.
4. If the power were to fail (or, more importantly, be turned off deliberately) your alarm would not communicate, at all.