I like the form factor and very clean slim design of the HC30, I hope that they will do a single AA version of this design some day (with less output of course). As always, I will not buy Nitecores because I can not stand cool white leds, even the sometimes used 3C neutral does not do it for me. So the led must be swappable and usually with Nitecore lights that is not possible.
I bought a second-hand HC50 a while ago with the intention of swapping the led to a warm high CRI one, and I have not found a way to get into the ledboard part. My current idea is that the last part of the assembly is that the lens is glued in (with no option to get behind it to even start trying to pry it out)
The surprising part of the HC30 is not stated Low Voltage Protection...but if I remember it starts stepping down (Not sure have not had time to work with mine yet)
Djozz - I think all of the manufacturers are going to go back to a AA/14500 offering. I know that one competing manufacturer has just made one and that another is considering so Nitecore hopefully will follow suit. They can still get 500-600+ lumens out of a 14500 nowadays.
BTW...these dogbone headlamps are relatively easy to mod...LED's and/or drivers
I bought it from FastTech, along with some 10, 25 and 45 degrees ones.
I’ve tested them in multiple lights and found that 45° is really useful indoor !