Pixhawk and underslung gimbals

So im gearing up to build a system using Pixhawk 2. The base frame is comprised of Trex 700 mechanics with a standard style head, not DFC. It has been stretched to 800mm and swings Align 800mm wide chord symmetrical blades. This helicopter also has a large gimbal that hangs underneath for carrying a DSLR, FLIR, SSD RAW recorder and other gear. Now it has been used successfully last year with a standard FBL unit on it, Spektrum AR7210BX specifically. After quite a few tuning and trim flights i got it stable in the accelerometer based “self level” mode so i could focus on positioning it vs having to focus so much on the act of flying. Aside from feeling like a flying cow it moved along quite well although i never attempted anything over 30mph or so im guessing for forward flight. Its more for getting high res aerial photos and videos and a pet project for working with a local municipality’s fire and police for uses involving aerial thermal imaging.
My question is, how will pixhawk respond to having a large gimbal hanging under the helicopter? Is this do-able? Im going to be using the pixhawk 2 btw. Im just wondering as ive read many posts about unwanted oscillations and from my experience last year i know that adding the gimbal made using a stardard fbl a chore to get rid of them.

I am flying a Trex 700 nitro with flybar stabilized head and a Pixhawk, carrying a gimbal and camera under it with homemade wider and taller landing gear on it. I have had no stability problems at all with it. The only problem I’ve had is smoke from the exhaust making it look like I’m flying thru the clouds sometimes.

I’ve heard some reports that the Pixhawk is better with a FBL head because it can get confused on what the flybar is doing. I haven’t had that problem here and am currently building a smaller 600 electric with a flybar head too.

I don’t know about differences between Pixhawk and Pixhawk2, but I don’t think there should be a difference.

I should add that my Trex 700 is not going to do any 3D or anything with a Pixhawk with the flybar head. But it sure flies stable - almost to the point of being sluggish, but still crisp enough to be easy to fly. If it’s easy for me to fly in Stabilize then I assume it’s easy for the Pixhawk to fly it too in Auto. I love the way it handles in the wind.