For me, the jury is not out yet. The first I heard of EUA, as silver, was when I got email announcing I'd been upgraded by CO when I changed a SAN-EWR return ticket from H (3-day advance) to Y. On my next trip (EWR-SFO) I struck out, and on my next EWR-SAN run, now as gold, I got EUA outgoing on a connection that I ended up missing, and EUA returning on a direct flight.

So, all in all, not bad, and I certainly don't miss staying up until midnight for what was proving to be about a 25% hit rate as silver.

I'm still peeved over their distinguishing H from Y, denying me upgrades far in advance in order to save my company about $100 on an $1800 ticket. As someone said, it is probably because CO knows there are companies that will enforce the purchase of the slightly cheaper 3-day fare. Aargh. Never got a response from CO about my comment to them, either, which is even more disappointing.