I did some measurements on the capacitive coupling of my bench meters to the mains ground (i.e. to the meter case in all three units)
for another thread on the forum here. The newcomer came on top by not a small margin, to my surprise:
Hioki DM7275-03Positive input to mains ground - 10V range and below <30pF, 100V and 1000V <10pF
Negative input to mains ground <30pF
Between input terminals ~1500pF for 10V range and below*, <10pF for 100V and 1000V ranges.
Here I can add that I also measured the DC leakage to ground from measuring terminals with my Keithley 617 electrometer: for +100V above the ground the leakage is 2.5pA, for -100V it is -6pA.
Cheers
Alex
* - possibly something to do with the contact checking feature, even if it is OFF. The cure is simple (if the input C is a problem) - to put a 10K resistor in series with the positive lead and use Hi-Z, on 10V and below the meter has ~20pA input current or ~0.2uV added error with the resistor.