The 9650 doesn't have metal gears. It makes no difference, as it is a KILLER 12th scale servo. I have two seasons on mine, still centers perfectly, and is more than strong and fast enough. I have in the past, used the JR3650, and the KO 951.

My current set-up utilizes a 2s lipo rx pack. I find the lighter and slightly slower Futaba to suit my driving and car set-up better than the KO. I haven't tried a 3650 on 2s power, but I know others that have and say it works very nicely.

These are the ONLY three currently available servos I'd consider putting in a 12th scale car.