however i have owned the Nova 528, RB 928, werks B7.28PRO, GO .28, Picco .28 and the Werks is the strongest of them all so far and then the RB...i havent had a chance to get the GO .28 broke in yet, but from what ive seen from the GO .25 i expect great things...on the track the GO .25 pulled the RB 928 was faster than the Nova .28 and kept up with the Werks .28...the ninja is an amazing engine, but ive never owned one due to heard to many breakage issues...