I have shipped formula to the resort. In June I brought my then 9 month old and I shipped down formula, 30 jars of baby food, diapers, sunscreen, wipes, etc., etc. I purchased 7 boxes of six 8 ounce cans ready to feed formula. It is expensive, but I would HIGHLY recommend this. I did not have to refridgerate it or warm it up. In the mornings I would just pack up a few empty bottles along with a few cans of formula. It didn't matter where we were - if the baby was hungry - I just popped open a can and fed him. There was some waste, but the convenience made up for it.
I did call Saratoga Springs ahead of time to make sure that this okay. I then shipped it UPS to myself in care of Saratoga Springs. The box that I shipped was 50 pounds and I believe it cost 28.00. It was too much worrying about flying with formula and glass baby food jars........this was definately the better option. It was a little costly, but to purchase these items at WDW would have cost me more than double. I think it was 3.00 for 8 ounces of formula and 1.00 per jar of baby food.
Everything arrived in perfect condition and they had it ready for me when I checked in. The convenience alone was great!
Good Luck in your decision!