As far as butchering servos, most modellers seem to have a surplus or a steady source of old servos with worn out gears or such like that are worthy of converting or hacking. I do not so what would be a good off-the-shelf servo to use for the Lindberg Diesel Tug or the Shrimp Boat (for example)? I am leery of using one of the current glut of cheap Chinese servos (the ones that are ostensibly directly from mainland China) that have no name because of certain unknowns or they might not be up to the task, readily or easily disassembled, etc.

I've heard that a standard servo provides, possibly, the most ideal propulsion motor and one shouldn't go smaller (in servos) than that for the typical 12-17" converted plastic boat but I've heard 1/4 scale servos are sometimes also good. Am I correct in my thinking?