I started getting some snow in the video @ 1.5 KM or so (ground distance) with 5.8 and 200mw. I'm not sure what the actual 3d distance would be but I was fairly high so at least a little further than that. There were some good rain clouds around and I chickened out once I saw I was looking down on clouds and rain around where I was flying
Great views but not so great for keeping things dry.
This is just on the outskirts of town and there are a lot of suspicious towers with various pointy/round bits sticking out all over the place so I highly doubt it is rf clean
(I can barely use 72mhz for r/c as there is so much noise and interference - 2.4 ghz is much, much better).