Bluelab has a PH check setpoint. So if it becomes uncalibrated it will let you know. Theoretically. I haven't had mine long enough to tell. But my Hanna combo meter didn't need calibration often. I checked every few months, but most of the time it was on point still.
Calibrating is a breeze. You just stick it in the solution and hit calibrate and 7.0 pops up and you set it. BAM. No turning dials to get the right PH.