Both lights are super bright and have plenty of brightness/flash settings for you to tune to your preference. They charge via USB-A (the old school big USB slots) which might seem old-fashioned but is actually pretty handy (no juggling cords and adapters, you can basically always find a USB-A slot somewhere).
1. The front light's battery life isn't excellent. Just taking a couple spins through the neighborhood at night using the not-ultra-bright setting brought me down to 50%-ish battery life. I have no doubt this thing could last through a nice night ride, but if you're spending a lot of time riding in the dark without opportunities to charge up you might be bummed.
2. The bands to attach the lights to the bikes seem a notch too small. My bike doesn't have weirdly-large tubes or handlebars and I have to really pull hard on the rubber straps to get them to latch. I guess this could also be considered a good thing, the lights do feel secure when riding.
The 500 lumens in the front are excellent; however, running at this setting the battery will not even last for 1hr. Quite the sad realization while riding at night and running out of juice while still 30 min to get back.