I have seen several video reviews of the Spark with the reviewer mentioning that the gimbal can't keep up in Sport mode and shows lots of horizon tilt, etc.
What they don't know and haven't read in the manual is that the Spark locks the gimbal to FPV view when its in Sport mode. For this reason it is like flying in fixed-wing mode every time Sport mode is on. Not saying that is good or bad, but that is what DJI has decided to do. It is probably related to the maximum tilt of the gimbal matching up with the angle (attitude) of Spark in Sport mode. If you notice, because of the weird oblong shape of the gimbal it can't tilt past a certain point without hitting the upper part of the drone.
What they don't know and haven't read in the manual is that the Spark locks the gimbal to FPV view when its in Sport mode. For this reason it is like flying in fixed-wing mode every time Sport mode is on. Not saying that is good or bad, but that is what DJI has decided to do. It is probably related to the maximum tilt of the gimbal matching up with the angle (attitude) of Spark in Sport mode. If you notice, because of the weird oblong shape of the gimbal it can't tilt past a certain point without hitting the upper part of the drone.