Nah, I'm a very happy bunny if my meters all agree with within 1 or 2 least significant digits, so if I measure 2.50000v reference voltage on a 3.5 digit meter and I get either 2.499, 2.50 or 2.501, on a 4.5 digit 2.4999, 2.5000 or 2.5001 and 5.5 digit get 2.49999, 2.5000 or 2.5001, does it really matter as long as I can trust the reading that I see to be within 1 or 2mV (or uV) of the actual value. I can select a meter that I know has the resolution that matches the requirements necessary for the job in hand.