I can't judge them in metric units. I find it interesting that you would use the 3.6 gram servo in a 3M glider. May I ask what surfaces were controlled by such a small servo and what plane they were in? Was this an e-glider, slope glider or a thermal glider. I might use that servo in a hand launched glider but not in a 3M glider. Even if it has enough torque to move the surfaces, I would be concerned about the ability of the gears to take the stress.

Interested in your application.