I'm flying a quad using 4108 480kv motors with 15 x5.5 props, APM 2.5, Arducopter 3.0 and mission planner 1.2.60. The quad was very stable with 12 x 4.5 props but with the 15s not so much. It acts twitchy at hover and has a wicked oscillation on rapid decent.
This is what I've done so far and I would appreciate some input as to whether or not I'm heading in the right direction.
Lowered Stabilize R/P P from 4.5 to 4.2
Lowered Rate R/P P from .1400 to .1200
I'm not sure how much change I can get away with before it decides auger itself into the ground.