Does anyone know approx runtime on the RRT-01 @ 500 lumens?
Also, I would think it might get a bit hot?
Anyone have any experiences with one yet?
I recall seeing some manufacturer documentation that listed runtime at 20 minutes on high using a 700 mAh ICR 16340 cell.
It's possible this light might pull more amps and is brighter using an IMR cell. It's also possible that the amps it pulls even on an ICR cell could exceed the maximum 1.5 amp draw from 16340 ICRs. If that's the case then it would be safer to use an IMR cell or perhaps a larger 18350 ICR cell that might be able to sustain a larger current draw safely.
I run my RRT-01 on an AW 18350 IMR cell. I haven't tested the runtime, but as far as heat goes... yes the light gets hot rapidly at maximum power. So much so that I would not recommend tailstanding at that power for more than a minute. If you carry the light in your hand, you can run it considerably longer at maximum power since your hand will help wick away the heat.
Note: If the light starts to overheat it will give a brief flash. If you see the flash immediately turn down the brightness. I had an older Jetbeam BK135a that gave this flash when it overheated and I didn't realize what the flash meant and left the light running, which caused permanent damage to the light.
In my testing with my RRT-01 I only experienced this flash when I tried tailstanding the light and letting it run at maximum power. When I saw the flash I immediately turned down the light (which did not suffer any damage). The body felt very hot to the touch. Note that I haven't tried my light on ordinary CR123 cells. At the lower voltage of those cells heat may not be an issue.
I like the RRT-01 for its small size, easy one-handed control, extreme brightness, and low low. But when filled with an IMR cell this is not a light I'd want to hand to someone unfamiliar with high performance flashlights.