NZXT Bunker
 

As such, even with the Bunker door closed and locked, if your side panels aren't locked, the Bunker is not a particularly effective solution. With a ratchet it was absurdly easy to remove, and, I imagine that it could be done with a pair of pliers or an adjustable wrench. If peripheral theft is truly a concern to you, consider supplementing the Bunker's function by locking both side panels.
http://www.overclockersclub.com/reviews/nzxt_bunker/