trying to understand the question, are you trying to decide between the Gen-2 and the Pro?
The Pro does everything the Gen-2 does and:
has a bigger/better keypad, so its easier to use.
has a backlit LCD (backlight in the Gen-2 is an option), the Pro LCD is bigger.
has closed-loop boost control
can run closed loop using the wideband for both part throttle and full throttle (gen-2 is full throttle only)
comes with the logging/tuning cable (the communication cable is an option for the Gen-2)
The Pro and Gen-2 each have a style of extender extreme chip setup specifically for them, so you would specify accordingly.
Those are the basics off the top of my head..
post back with more questions, and some details about your car.
Bob