Had RPM install mine last weekend. Excellent install, very clean. $160 plus tax and took just under 2 hours ( I went for a long walk and bought my Compass card at Royal Oak station). Works like a charm. Goes into parking mode after 5 minutes or so and then only turns on when something moves close to the vehicle. No apparent impact on 12V battery and no chance of draining, especially as it’s constantly charged by the big battery.