i have tried the mugen MIP in mine.. they work.. i just havent tested enough to know weather i like them better or not than the stock pistons.. right now i have been sticking with the 6x1.3 pistons.. with 3 of them drilled to 1.35.. both front and rear.. 550-450 shock oils.. its been so dang hot lately.. and summer time weekends on the water.. i havent got to really try much in the piston area.. i have been wanting to on the new MIP pistons..