It seems the real advantages of the I2 are recording speed and workrate flow. The I1 is easily adapted to carry auxiliary batteries and an fpv camera. Obstacle avoidance is, to a lesser degree, a gimmick IMO.
Some people actually understand what they read about new technology and how to find trustworthy resources for information. Enough to make sound decisions.
Having one and finding out to pay for stuff I will never use doesn't cut it for me. I need to know before I buy one. The camera, now that's the whole thing. It will make me want/need to have one probably.
Not the copter. The I1 is as good as I need for flying.
The X3 and X5/X5R Will not work on the I2 and the mounts have totally different data paths On the I2 the X4 and X5s "Camera heads" are sensors with lens mounts all the signal processing and recording is done in the Airframe NOT the camera body. The X3/X5/X5R are complete camera and recorders in one unit.