At the end of the day it's a deterent, anyone who wants in, will get in, hit and run, they'll grab what they can quickly, this is more likely to be a problem in a property that is secluded from others, gives them more time, best we can do is hope they'll go somewhere else that hasn't got a sounder/bellbox outside, even with a 'monitored' system there is still that 'timeslot' unfortunately, and the tossers know that.