what a great budget tuner... have the polytune mini on my board, but when using the HD500X i use the Joyo in front as it is super visible and can be used with a 9v battery too!
Works just as well as the Korg pitch black. Not as bright, but unless you are on a completely dark stage you will be fine. Accurate tuning with 4 different modes to choose from. I use it as an always on tuner through the tuner out of the volume pedal.