After my M3 is gone, I have an ESS direct flash unit up for sale.
it has 3 files installed:
ESS performance tune
ESS performance tune catless
ESS performance tune catless + rev limit 8600 rpm
Its a complete kit, with cable and usb stick for pc install of the software, usb cable to connect to your pc.
price: 700 USD air-shipped to US (I am in Germany so shipping is not that cheap)
For question just pm me.
cheers and happy new year to you