Yesterday I switched my ecu with one that I bought from JDM-BB4 (fitted with one of Robs chips

the car runs fine, with no bogging, hesistation or any apparent issues, and I dont get a CEL either. Im really just trying to make sure that the unused plug isnt anything of too much importance!
..and would I be right in assuming that the chip can be removed and switched between ecu's? (unfortunately not something Id be comfortable with trying though!)

Thanks.