I’ve been running a Knog 4V Standard taillight for several years now, and it just won’t die. It’s been submerged, run in snow, salt, sand, mud, gravel, dirt, dust, rain, rain rain rain rain rain rain rain, 110 degrees and -37 degrees. It’s been a great light.
As can be seen, it has not lived an easy life thus far.
I typically run it in a flashing mode, and easily get 4 hours of burn time out of it. I haven’t run it down to dead to see what the total battery life is.
It has shown itself to be reliably fully waterproof, and thus far has proven to be as durable as my old 4V. The real advantage of this light over the 4V is the larger LED at the bottom; that LED is angled slightly upward, so that when mounted on a seatpost, it is pointed straight at drivers behind you, increasing visibility. The 70 is significantly more visible from the rear than the 4V, and that makes it a worthy upgrade in my view.
Charging is via USB, with a flip out, integrated charging point–just like all of my other Knog lights. Genius.
Thus far, I have nothing but good things to say about the Road 70; I’ll update this in a few months after I have more time with it.