i can't vouch for performance gains from the injector spacer, but it was cheap and i said wth...
the charger would be my pick for the item i liked the most.. really opens up the airflow...
tho the adj reg works fine and is really a nescesity for getting performance up, it can be a pain to adjust.. i may change it out at some point for a vacuum reference one.. haven't done the research on them yet tho...