well both my uncle and my friend have 2000 civic si's and both have the Greddy kit, my uncle had his now for about 3-4 years, my friend had his for about 2years, and none of them ever had a problem, both of them have done a port job, pistons,rods,cams,valves and springs with retainers, and i havent seen my uncle ever loose a race to an fellow honda or acura , even this one guy who said he was pushing 12psi on his H22 prelude with an huge IC and my uncle still beat him, so if you want performance and durability go with Greddy....