I have used the exact same unit at three different houses. In all cases they worked well, once I got the kinks worked out. I mounted my remote sensing unit inside a birdhouse for disguise, and other than the pesky bluebirds in the spring, they never "falsed" too much. My current set up is probably close to the limit, at about 200-300 feet, but is starting to fail (five or six years old?). May need a new one. The winters here are death to batteries too, but such is life.
Here is an old post, with some pictures I took:
I bought a Bluebird Nest box to hide the remote motion detector, and added a nest box predator guard to focus the motion detector and further disguise it. Our property is covered with bird nest boxes and bird feeders, so this one just blends in.
The motion detector is mounted inside the swinging door with Velcro, the door swings closed and is clipped, and the homemade security system disappears.......