We have one at bedside, one in the kitchen, and one in DD school backpack. I have read that it's best to use the same one all the time, but that would be so inconvenient for us. It would mean remembering to bring it upstairs every night so we can do middle of night checks and remembering to pack it into DD school backpack everyday. I have checked each one for accuracy and they all gave bg's in close range of each other, although I know they can differ with each check. How many meters do you have/use?