[jagasail]

Sort of depends on how complex your setup is and how many instruments you have attached. For just a few a USB hub is fine, but with several instruments, particularly if you have more than one or two sending nmea data, a multiplexer is better because it can act as a traffic cop over the flow of data. For me it's particularly useful because I often have more than one instrument transmitting GPS data (seems everything has gps these days) and it will prioritize and only pass one of them on so they don't conflict. I can control that priority. It also acts as a translator from Raymarine's Seatalk to nmea (my wind/speed/depth are Raymarine).

Scot

edit - should also add that a usb is fine if you're only attaching usb devices, but many of us are using the multiplexer to integrate all of our instruments, most of which don't have usb.