Btw, one thing you can do if you really want to save on drill heads, is put in efficiency modules in the mine. Since the drill head is used as fuel, with the max -80% efficiency, you can produce 5 times as much ore / drill head (also works with the big-mines and mega drill heads). Thank you for you...

I'm not sure whether it's a bug or not, but I was disappointed when I noticed that a Niobium Mine on a Niobium Ore patch resulted in roughly the same amount of Niobium Ore produced per consumed Drill Head than a Ground Borer. It also seems to be slower. I tested it by measuring the output when suppl...