I still recommend pci nics over usb.
If I had only 1 machine and it was in the same room, I would also consider nics. As it is, I believe WiFi will meet our needs. The CISCO unit from COX has 4 LAN ports so this should also meet the need for a phone in the living room. With only this modem I would have no need for a Router. My Motorola only has 1 Lan port so I needed the router for extra connections.