BOTH COMPANIES HAVE A REPUTABLE AND POSITIVE BACKGROUND AND CHOOSE WHO EVER YOU FEEL COMFORTABLE WITH,PICK UP THE PHONE AND ASK EACH TUNER CO. AS MANY QUESTIONS YOU WANT REGARDING PERFORMANCE,DYNO RESULTS AND ETC AND TAKE IT FROM THERE,WHO EVER RESPONDS TO YOUR QUESTIONS ADEQUATELY AND PROFESSIONALLY GO WITH THAT COMPANY,YOU COULD EVEN DEBATE THEM,LIKE HERE ON THE FORUM,CASE CLOSED,THANK YOU.