The thing that makes this one special, other than the attractive price, is the possibility to connect an external power supply.
Others don't have this option, so most USB-devices will only work with this one, if they need more than 120mA to operate - Which almost all USB-devices do
USB isolators protect your USB devices!
The USB isolator ME-USB Iso was designed to protect a host with USB interfaces and the connected USB device. It protects the equipment from voltage peaks and avoids ground loops.
It can help to eliminate noise from ground loops or potential differences for example in audio and video applications.
The isolator is fully transparent (like a cable) between the PC and a USB device, so no additional drivers or other software is required.