Not quite that, but something similar. I fitted a pair of 5 lever dealocks, which fitted to the sides of the doors, and needed a hole cutting for the bolt to pass through. Lock is on the front of the door, and bolt goes into the timber support at the sides. Very secure, but like any security if they want to get past it they will, but only by making a big noise with a lot of hammering.
Only downside is that with the central lock there are now three locks to do/undo, but if we're around we leave it on the central one until we're finished for the day. Always lock it by 6PM at the latest just to stop the scrotes who found their way in once over.
If you can stand the hassle of extra locking operations then they are good. if you're a bit lazy and can't be arsed with all the pfaff then find something else – like a gun!!!
