Why are 5g servos so much more "uncommon" than 9g servos? It seems I can find pages and pages of 9g servos to buy just about anywhere. Either individual or in bigger quantities. I would expect one could do the same with 5g servos (in theory it seems like a good option for lighter aircraft) but they just don't seem to be as plentiful. I have some 3.7g servos but wouldn't mind having some more 5g ones around too.