Here's the potential problems I've seen:

* Flights before 7 a.m.: Since a lot of the ticket counters do not open until 5:30 a.m. to 6 a.m. (or even later), there may be long lines for the first flight of the day. (But since you have elite privileges, you won't be stuck with this wait.)

* Random hand checks of checked luggage: These stations have been understaffed at some airports. Combine this with the rush to check in for the first flight in the morning, and you may have a mess. I waited 40 minutes for a hand-check at SJC before a ticket agent came over and told me to board the plane and that my luggage would follow on a later flight.