The statement that a mechanical gauge is "more" accurate is bs. Dredknut, take a look at your "more accurate" mechanical gauge. How accurate is it when it has been off "0" since day one? It's because the calibration of mechanical gauges from the getgo or over time is horrible. Think about it. The more moving parts you have, the more you're prone to failure. A mechanical gauge is full of moving parts because it needs that pressure to give the needle a readout, not to mention the longer vacuum line you have to run. A longer line equates to a pressure loss. Not very big, but it's still there. Along that vacuum line also, you could have potential leaks due to a number of reasons. I'm sure electrical gauges have its possible problems as well, but they have yet to be heard of since they're still pretty new. With mechanical gauges we all know the problems that they have.