I haven't had but two or three failures in my career and I feel that they are pretty cool devices. Having one on a circuit in my carpeted house is overkill, having them outside and in wet locations, prudent.
We had some 25 amp made especially for our signal systems and they had surge protection built into the assembly. Overkill maybe but, with 4500 computers in vented aluminum cabinets installed outdoors and protecting folks from exposure to shocks and the computers from all sorts of chip killing situations, cheap insurance.
