Last week I flew out two miles with my camera boost at 19. Had five bars all the way out. Then I turned around and flew back.
It was the first time I flew out that far and didn't lose FPV.
Yeah, I am a little concerned about overheating. It was a fairly cool morning though. But the thing is, we don't see a lot of threads on the camera's tx board overheating, so I'm thinking DJI was a little conservative with the 13, and maybe we can push that a bit in most cases. Still - we should be wary of hot days of course.
OTOH if we have to buy a new used FC200 on eBay, it's not the end of the world.
Edit: Another strategy - if it's a hot day and you're worried about overheating - is to fly out with the normal 13, and then when you're half way out, hover and enable the boost. That way it has less time to overheat. I watched Chuck of DBS Mods do that on one of his videos.
Do you remember your range before FPVLR stage 4 on the RE700 ? with the VISION.