I like both but seem to prefer offsite lately. This weekend my sons and I are staying one night at an Amerisuites I paid $28 for on Pricline. We'll get the two rooms, hair dryer, iron and board, fridge, coffee maker, microwave, and free breakfast. At Po or AS, I would paid $89 or $49 with a Florida Resident's discount and received none of the above. Had I paid full price for the Amerisuites, it would have cost $69. We're planning a Christmas trip and still can't decide what to do. Last Christmas, I paid $50 for the MOWC which was a beautiful resort.
I would make sure my offsite hotel was not far from Disney and factor in the price of a rental car if you're not driving. Good luck making your decision.