Managed to pickup two of these from jaycar in the weekend.
Only 3 wires, de-soldered them from the circuit board that it came with, then hooked those 3 wires up to +5v, ground and a gpio pin on a raspberry pi. and presto, got a working couch pressure presence detector.
works really well under a couch cushion, no false positives. cat doesnt set it off.
no need for a any resistors, just 3 wires to a pi (had a pi as im trying room assistant aswell, otherwise I woul duse a esp32 or pico w or something).