Black diamond lights will eventually fail. Petzl lamps are too pricey for their performance and the fact that you have to buy their rechargeable batteries.
I bought a nitecore hc30 about 3 years ago now and it's still going strong and I don't think it will ever die. It has taken a real beating when canyoneering. I also use it constantly for working at home, running, camping, hunting, etc. It uses a single standard 18650 battery or two of the short fat ones. It's incredibly lightweight for it's battery life, power, and durability.
The only downside is that it doesn't have a battery charge light indicator or a red light. I have a backup petzl that I use if I'm really concerned about having a red light. I know some people will also use a piece of red cellophane tape to filter it red. I have an extra battery, so I just use one battery for a couple months and then switch the battery out and charge the other. I bought a battery charger for mine, but I believe they make batteries that have a micro USB built in, so you can just plug the battery in directly.
There's also a similar model to this that has a red light, hc65, I think. It also has a built in charging port and battery charge indicator light. But it's a bit heavier and the run time vs beam intensity numbers aren't laid out as well, in my opinion. I'm sure they have some other new models at this point.
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