We actually considered that as an alternative in the beginning, i.e. use a bunch of usb2serial adapters on a 1U rack-mountable USB hub.<p>We decided to go for serial ports because that ultimately is less clutter in the rack, i.e. the usb2serial adapters “go into” the unit instead, and you get to use rj45 connectors instead of bulky db-9 connectors.<p>That said, of course a generic usb hub could satisfy more use-cases. What’s yours?