I have been trail running before sun up for a few years now. I have gone through many headlamps, and have a lot of experience with em. I don't like any of the headlights that have a battery pack on the rear of my head. Some like em though, but not me...too bulky. I run 4 - 12 miles on mostly trails in the middle of the woods where it is pitch black much of the time.
My favorite set up by far is the Zebralight H600 with the NiteIze headband (sold seperately - The zebralight headband is way too bouncy.) The headlight, battery, & niteize headband are comfortable & lightweight with excellent runtimes & output. I love the awesome output, and the runtimes are perfect for my longer runs. I also like how floody the light is though it is not too floody like my H501w (pure flood.) Many of my headlights were not floody enough which gave me tunnel vision because of the tight hotspot. The hotspot of the H600 is nice and broad.
My favorite headlight for short runs (and now my favorite all around camping light) is the Zebralight H51F or the H51Fw. This is a single AA light with plenty of output for most situations. I find this light to be perfect for camping trips as well. It's bright, mostly floody, & has just enough throw to be very versitile (it's not pure flood & does have some throw.) I like it for some of my shorter runs during the colder months. However, during the warmer months I need the extra output of the H600 for spotting spider webs....I have face planted into too many, and prefer extra output to spot em early.
I also carry a handheld light for backup. Wnen I want to travel light I carry a Quark AA (now called a Quark QPA - single AA light.) Most of the time I carry either an Olight M21X for some good throw or even my larger EagleTac M3C4 single XML for even more throw......yes it's too large for running with, but for me it's worth it. I spot coyotee, dogs, deer, & other critters regularly, and like seeing them in advance. It's all a whole lot of fun to me though, and sometimes my lights are overkill. The Zebralight H600, however, is a necessity to me, and is likely to be my go to running light for some time to come.
Here's another thread on the subject if you haven't seen it -
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