A good friend has had great success with the motion activated sprinklers. What he found was that he needed multiple ones covering the same locations so that when one went off, it would set the rest off in a domino effect. The big thing when using multiple impact sprinklers is being sure you have the gpm available to cover all the heads so that it still has enough flow to be effective when they all go off.
Why do people not respect us as they do other tradesmen? Because every Tom, Dick, and Harry doesn't think he can be a plumber or electrician!