Old style Koryu Karate structured around the Naihanchi boxing system, Passai Boxing system and the Aragaki Seisan Boxing system.
Learn and study karate in the fashion as it was practiced in Okinawa, and before that in Fujian China. Practiced for genuine self defence learn the "Koryu concepts" of old style karate.
Check out YouTube channel "Mark Bonner".
I (Mark) teach regular seminars of Koryu Karate at other dojo, and have many club owners who come and train to better understand their Karate, regardless of style.