Can’t comment on that specific one but I’ve got a top cap mounted usb charger and you can either piggyback but especially if you’re light has a switch else it’ll take forever to charge as it’s only getting some of the power from the hub, and some to the lights (which will also suffer)
I wired mine up to a simple three pole electrical switch and some Sugru to make a housing so I can choose off, light or usb (charge in the day, lights at night) which is housed in a small top tube bag
Can’t comment on that specific one but I’ve got a top cap mounted usb charger and you can either piggyback but especially if you’re light has a switch else it’ll take forever to charge as it’s only getting some of the power from the hub, and some to the lights (which will also suffer)
I wired mine up to a simple three pole electrical switch and some Sugru to make a housing so I can choose off, light or usb (charge in the day, lights at night) which is housed in a small top tube bag