Join Date: Aug 2006
Location: DCA / WAS
Programs: DL 2+ million/PM, YX, Marriott Plt, *wood gold, HHonors, CO Plt, UA, AA EXP, WN, AGR
Posts: 9,386
1 PM should be a non-issue. I do it regularly.
Early check-in (early morning) is most useful getting off a red-eye - particularly an international flight to Europe. I've had pretty good luck with that, too, depending on the hotel.
I always flag my reservation for early check-in. If it's critical, I also call the hotel directly.