I shipped a box to myself at the hotel two years ago and it was great. We were travelling with a 2 and 10 month old. We shipped formula, diapers, wipes and breakfast and snack foods ahead of time. Less to lug at the airport. It was the best $13 I ever spent.
I just talked to a friend who got back from Florida last week. She shipped her luggage to her hotel ahead of time so she wouldn't have to deal with Baggage Claim. She shipped UPS and when she shipped the box out, she prepaid to have the return label printed. So when she was ready to leave, she dropped the box at the front desk and was done with it. She didn't even have to box up the suitcase - they took it "as is."
The key is to ship it so that it will arrive a day or two before you do. Then call the resort either the day before you leave or the moorning of your arrival to make sure it got there. That way, if there's a problem you can bring the stuff that didn't make it.