Thank you. Let me just say that, in comparison to other lights mentioned here, there is simply no comparison between a light that is well over 100lm and one that is well under. E.g., a 65lm taillight vs a 160lm taillight? There's just no debate.
Once you get a REALLY bright taillight, you won't ride anything else.
Some lights do better than others. Lumens is the right measure to use here, but it's often incomplete because lens design plays a big role. But this is much more true for headlights than taillights. That's because you are using the headlight to see, so where the light ends up matters a lot.
I.e. a 900lm headlight can actually be much more useful than a 1200lm headlight if the lens design is better so more of the light ends up on the trail.
But for a taillight, the same logic doesn't apply. In the case of a taillight, all you care about is how much light is being generated, which is exactly what lumens tells you:
https://en.wikipedia.org/wiki/Lumen_(unit)
So, basically, for headlamps, you need to consider both lumens and lens/reflector design, because the way the light illuminates the road/trail matters a lot. But for taillights, all you care about is lumens. Brighter is better.
"Non est ad astra mollis e terris via." - Seneca | rappstar.com | FB - Rappstar Racing | IG - @jordanrapp