I will be using the 540 over Ethernet for my first race tomorrow. Set-up was easy once I dealt with an IP conflict. With SST if you are set to LAN but don't have a timer connected, you will get a cascading error message from a network timeout.
For more images and a few more comments, visit:
http://timingguys.com/eve/forums?a=albumtopic&TOPIC_OID...1033832&f=6396068411
Jenna