If you go to Martelli website they list which shows they will be at...and when.
You do not have to use the Martelli blades - but the blades do have to have "JUST" a circle in the center. Not the notched ones. It is best to have it demonstrated becuase I was holding mine wrong and then I wore out a part (that they replaced for free). Nice people to deal with. Sign up for the sales too - they are the best deals I think.