I ride only in the daytime, bought this for its 1000 lumen daytime flash mode and 7.5hr lifetime in that mode. Very bright and its flash sequence is definitely attention-grabbing. Given that it has 8 modes, it's great that it "remembers" the mode you last used last. When you head out for your next ride, you simply hold down the power button until the light turns on, about 2 sec. When you finish, just hold down the button again until the light turns off - easy.
A few niggles:
(1) gotta pull hard to fix its rubber strap around the handlebar, helps to rotate the light 45-90 degrees on its mount
(2) to avoid reflections off the screen of my Garmin (on its "out front" mount), had to mount the light upside down below the handlebar, putting the power button underneath the light where I can't see its state of charge indication - move the power button to the rear of the unit (or have dual power buttons, top and bottom?)
The light is great, but the bars on my bike is one of the wide-ish ones and it's not as easy as I would like to pop this light on and off when I park the bike. Be forewarned. You have to reeeeeeeaaaaaallllllllly stretch it,
I read up on a lot of lights and feel like this one has great options for brightness and the battery life is good. Like that you get a battery warning at 50% so you don't get caught out. My only complaint is the strap is short for thicker handle bars ... can barely get it on.