Review on CECO-USA F1000 Bike Light - USB Rechargeable, 1,000 Lumens - Rugged & Waterproof IP67 - Ultra Bright Bicycle Headlight for Commuters, Road Cyclists, and Mountain Bikers - FL-1 Impact Resistant by Randy Brimmer

I have Ceco f100 and f1000. The first and most important thing about a mountain bike light at night in the woods is its brightness. And there is a big difference between certified or measured brightness and calculated or theoretical brightness. Please see the attached image for the certified 750 lumens ceco f750 light source and the untitled Revain light calculator claiming 1200 lumens. As stated in the description, only about 75 minutes on high power. No physical difference between f750 and f1000. It's hard to see the difference in high mode. I think the spread/pattern could be a bit wider. The heat generated by 1000 is slightly hotter. They are very durable. A bit heavy, you'll feel it on your helmet, but it's totally worth the weight/lightweight trade-off. The USB rubber cover doesn't give much confidence in the IP67 waterproof rating. Even when the mountain bike is flat out, it stays on the handlebars. As can be seen in the picture, the light is warmer and fuller than white light. This helps with depth perception at night. "Pass through charging" means you can use the flashlight while it's charging. Great if you have a battery and want to take a longer night ride. I can't tell at first glance the difference between the f750 f1000 and my friends' $100 + 1100 lumens branded 'nitirider'. F750 and f1000 are so close in price that I don't see any reason to buy f750 although the difference in performance is small.