I've used two Lume Cubes in the past for my old P3P.. I also tested them to 5 miles at night--flashing them from a bridge with street lights while my dad drove to the top of a hill 5 miles away to look.
However one would overheat and shut-off at around 10 minutes. I sent it back and they sent me another one that would overheat in 15 minutes instead. I think they're great for their original purpose--underwater camera lights/flashes for go pros; but with the overheating, and loss of 5 minutes of flight time, I ended up giving them away to someone that lives much closer to tropical reefs than I do. I never had a compass issue with them--that was something I checked when I first got them and didn't notice any variation in compass bias with them when on or off.
I now use Firehouse Arc IIs which basically seem to have the equivalent of 4 strobon cree lights (which I also had at one point) on one circuit board; and I have four (equivalent of 16 Crees) of those on my P4P--so they're very bright and can be arranged so that the lights are viewable from more angles than the two Lume Cubes ever could.
However one would overheat and shut-off at around 10 minutes. I sent it back and they sent me another one that would overheat in 15 minutes instead. I think they're great for their original purpose--underwater camera lights/flashes for go pros; but with the overheating, and loss of 5 minutes of flight time, I ended up giving them away to someone that lives much closer to tropical reefs than I do. I never had a compass issue with them--that was something I checked when I first got them and didn't notice any variation in compass bias with them when on or off.
I now use Firehouse Arc IIs which basically seem to have the equivalent of 4 strobon cree lights (which I also had at one point) on one circuit board; and I have four (equivalent of 16 Crees) of those on my P4P--so they're very bright and can be arranged so that the lights are viewable from more angles than the two Lume Cubes ever could.