this topic has been beat to death over the years. But FMIC hands down, especially if you plan on modding the car more. SMIC is ok, but it heatsoaks pretty quickly and you will definitely notice the decrease in power. Some will say with a FMIC, you will lose throttle response with the longer piping and bigger core. But honestly with the stock GT25, the quick spool makes any change in response barely noticeable and you have no chance of heatsoak with a FMIC exposed to incoming air from the lower bumper area.
