Is there a limit to the number of times one can flash the MTH software between stock, and tuned or between various octane files if one has them? I find myself switching between my 100 octane and 91 octane files often when I want some fun and decide to fill up with 100.

 

There is no issue that I am aware of.

 

Eventually you will find the flash limit of the chips, but its in the many thousands of flashes. Don't worry about it; keep doing what you are .