Yes you should definitely have one! Here's one reason alone...I just got discharged from a myasthenic crisis. I had to have a spinal tap while in. The anesthesiologist who did the tap took the time to tell me that if I ever need surgery or anesthesia for any reason it's imperative I tell them I have MG, because anesthesia can have deadly complications.

Imagine if you were in a car accident and needed surgery, or something like that. For that one reason alone they need to know you have MG. There are many others.

Now with that said I really need to get a bracelet myself!