In my audio box I have a lot of things, one of them is an extra handheld microphone. This is a Shure SM58 that has an on/off switch. The reason I have the switch is so that sound guy can leave that channel on and I simply switch in on or off as needed. That way I won’t have the delay of the sound guy realizing I’m using the mic and him turning the channel on.
If the venue has a handheld with an on/off switch I will use theirs. However I did an event recently and their handheld microphone sounded like talking into a marshmallow that was inside of a metal can. I plugged my Shure SM58 into their cord and it was much better sounding!
It doesn’t take much to travel with that in my audio box and it comes in handy much more often than you’d think!
-Louie