I have found the Inspire 1 is much more susceptible to interference and lack of LOS than the P2 with AVL-58. When I flew from an open field with no obstructions, I was able to go 910+M out before it started to lose signal. I got up to 950M at one point. The final 3rd of that flight was over houses etc. But when you look at the video (below) you can see when the camera is pointed back at the home point that when it is over those houses etc. the aircraft actually has a completely unobstructed
view to my tx pointing at it. That is because it is high up (400 feet). With the aircraft on the ground, I am lucky to get 150M out of it.
In my first test flights, I had the craft up high too and there was mostly a clear path to it in the sky. But not always, sometimes a house or car would get in the way. In those flights I was limited to 500M.
The antenna orientation must be spot on too. In my ground tests, if I veered even slightly to the left or right of the aircraft, the signal dropped right off. It didn't fail, but it was enough for a warning. At less than 200M!.
I had none of these issues with the P2, but that's analog video. It gets snow in it and so forth, but you can still see. With the Inspire, when it drops, it drops.