I booked our family trip via costco and i think we got a good deal. We're going mid July, 7days.
some of disadvantages:
No Disney Magical Express (DME) - Ok with my family
No Dining Plan - Ok with my family
No charging to your room with the Magic Band, Magic band is additional cost, but ticket can be linked to band - we're ok with this
There is a resort fee - included with the costco package
There is a parking fee - we're not renting a car
No garden grocery delivery -
I'll see how hard it is to get to the Hess station to stock up on some drinks/snacks.
Advantages:
You still get to use the Disney bus system to the park
Extra Magic Hour
FASTPASS+ like a Disney resort - make advance reservation to attractions 60days from visit.
Free parking at Disney theme park with room key
Purchases from Disney gift store can be delivery to the resort.
I think if you can live with the disadvantages, you'll be able to save some money at your stay.