I've still got an FCC 2.5 in my SR15
basically their armature is decent, it DOES last on a 3s lipo
other issues include;
pinion gear made of creamy havarti
two bearing design instead of standardized 3 bearing design that systema uses
low torque compared to other motors
upon disassembling, I found the upper and lower heads were unmachined castings. The bearing in the motor head was actually fairly loose, which is where the overheating issue comes from.