Keith, do you unplug your guitars between use? I thought the active battery life on the Silent Circuit was something like 1000 hours - that's three hours of playing every day for almost a year before the battery dies... I'm sure that piezos and EMGs would drain the battery faster, but with the Silent Circuit, the only thing that happens when the battery dies is the circuit stops working, so the 60 cycle hum on the single coils would increase slightly - depending on your playing environment, you might not even hear a difference... I change my Silent Circuit batteries very, very rarely - once a year during their annual Full Tear Down & Clean Up®kbaim said:I change em every month or two.