It's been said that the P3 holds it's position better with VPS turned on. I did a prior video that I think showed that it does nothing when the P3 has a good GPS lock. Let me be clear, I'm talking _only_ about the downward facing camera and not ultrasonics. It was mentioned in this forum that the P3 hovered with less movement with VPS turned on. So I decided to do some testing on this.