For the same $99 you spending on them night guard things, you can equip yourself with an electric fence guarding the entire perimeter of your enclosure.
I keep my chickens in a light wire enclosure, this enclosure would easily be violated if not for the electric fencing. I have never lost a chicken guarded by a charged wire. It does take some thinking and some upkeep, but it is 90% fool proof. I say 90% because nothing, really nothing is 100%. Bobcats, coons, foxes, coyotes all make their living busting into places they ain't suppose to be, given long enough, they could and would bust into a bank vault to get your hens.