At what temperature range?
Anytime you have electronics involved that convert a voltage to a reading, one really needs to take the temperature coefficient of the tool if expecting "ultra precise" results.
Some may be fine in a laboratory environment, but may differ significantly in the temperature ranges the tool may actually be used in.

I used to build optical oceanographic instruments that used an LED of a specific wavelength for a light source.
LED's tend to have pretty wonky temperature characteristics and it was supposedly "impossible" to temperature compensate one.
It turns out most of the cheap electronics are not too good in this respect. My "free" Harbor Freight voltmeter reads 8% high. That's about 1 volt difference on a 12V battery. That's at room temp- Who knows.....

Put your tool in a baggie and stick in the fridge for a 1/2 hour and test vs. the same tool laying in the sun.

A simple digital display is +/- 1 digit + a % error that varies by the quality of the display.

Not venting on your specific tool, but just in general to people that assume if its digital, it's spot on perfect.