iTach Flex WiFi vs IP

What are the advantages / disadvantages to the iTach Flex WiFi vs IP other than the need to be attached by a cable?

We provided a run-down of the Flex advantages here:

configuration-and-setup-archives/itach-wi-fi-to-infrared-adapter-vs-flex-t9412.html

The Wi-Fi versus IP models are only different in that one uses Wi-Fi and the other uses Ethernet.

Thank you.