Etha W.wrote a review of Black Diamond Iota Headlamp on April 11, 2019
Familiarity: I've put it through the wringer
This is a headlamp well-suited to wearing around camp or urban running, but the brightness and beam distance makes it subpar for climbing, hiking, or other extended after-dark activities in the mountains. In fairness, the product specifications make it clear that it ranks below average in brightness and distance, but if (like me) you were in a rush to buy it and were not yet fully conversant in what different lumen and distance ratings feel like in the real world, you might find yourself a little disappointed.
Ultimately I'll still take this as a back-up or on a trip where I really don't expect to be doing much by dark; but on anything where I'm likely to climb/hike/ski a substantial amount after dark, I'd want something more powerful.