Of course it also depends on the calibration of the gauge and the have r and r.
I would stick with one gauge to reduce errors.
That made me smile and reminded me so much of the need for consistency of measurement......whenever the nurse took my blood pressure it was always lower than when my Doctor did, they both use different machines..........so I agreed with my Doctor that we would measure any change over time based on just using the one machine readings......so it didn't really matter how accurate it was, (except for my actual state of health) it would still measure change.
regards
John
