I have a now discontinued Petzl. The key feature for fettling (for which is gets used frequently) is that it has a wide, diffuse beam that gives lovely even illumination. There's also a brighter, more focused beam that's occasionally useful when you need to peer into crevices to see where the pingfuckit went, but is generally more useful for cycling. It does that reactive-illumination thing, too, which is great for camping, but not always ideal for fettling.
USB charging is also a win for fettling purposes, as you can keep it topped up with less faff than odd numbers of AAAs.