Fast and accurate operation. Brassard very "pro" comfortable and strong fixation. Only use the buttons to switch users before taking the voltage is a little confusing. If you press ON / OFF voltage tap will start immediately on the last user without possibility of change, We must again press ON / OFF to stop if it is not the correct user and do not save the measurement to another user. To verify or change the user must press "set" and then + or - to change the user (1-4) then press ON / OFF to turn it off and ON / OFF press again to take the voltage and storing the correct user. Ditto for the visualization of each user's history Another small drawback, it can not delete a measure of the history but all measures. So a tip, always press the Set button to verify the user before taking a measurement.