I've finally got this built into the final configuration it will have. I previously had the ESCs in between the main frame plates and the 3 wires from the ESCs to the motors inside the arms, but the heat they generated collected in the dome, and heated it up to ~50+ deg c, so I just rewired to have the ESCs on the arms. The excess wire I removed weighed over 100g so there was a good saving made.
Motors are sunnysky 2814-11
Props APC 12x3.8 top, 12x6E bottom with the rear pair of motors turning the opposite directions to the front, and the rear pair are also tilted about 2 degrees anticlockwise.
The brushless gimbal is running an Alexmos board, with rctimer 5010 motors, and the gimbal is handmade from 15mm wide aluminium bar.
I should probably redo the dynamic calibration since there have been a lot of changes since it was first done. I'm having trouble getting position hold to hold accurately, there is a small amount of wandering laterally, and in altitude, so hopefully redoing this will help.