BMW S55 Controller Issue
 

Hi,
I have purchased methanol kit a year ago for my BMW M3 F80 (S55 engine) i got the HFS4 V3.1 controller installation is perfect and the kit worked well, till today i changed my car's setup which required more meth to be sprayed so i changed the setup in both the gauge and controller, i had 2 choices either to get more meth sprayed or make it spray earlier i tried both ways and failed to get the required capacity of meth. So i decided to use my friend's controller installed on his Golf R MK6 the controller's settings were on default, i ran the car and meth was working perfectly as i wanted it sprayed enough meth. I compared both controllers and found no differences between them from both sides and versions except for the rectangular piece on the front face of the controller.

Going to my question i just want to know if i can buy the same controller for my car and will it be applicable and safe to use?

Thanks.