I have just bought a Zero4U usb hub. The card works fine, but it use some power. Without devices connected it use almost nothing, but with a mouse or keyboard connected, it use far more beyond what the mouse / keyboard draws.
Raspberry Pi Zero + Zero4U without mouse / keyboard (idle) = 0.5W
With mouse or keyboard (> 100mA) connected = 0.9W!
I just think it's worth paying attention to ...