I think this question depends on the personality of your own family. We're a family of 4 (dad, mom, boys - 8 and 4) and were travelling with my wife's parents. We flew in, preferred to stay together, and preferred to have a van in case we wanted to do some other things. Because of the age of our boys, Extra Magic Hours were not on our wish list.
Having stayed at the Caribbean before, I compared 2 moderate rooms to Windsor Hills and found there simply was no comparison, on paper.
We rented a 3 BR townhome. Wife and I had king BR, 2 young sons shared a professionally decorated Mickey BR with twin beds, and wife's parents had queen BR on main floor...all ensuite. Lining room, dining room, breakfast bar, full kitchen, patio and splash pool, full size washer dryer.
With van rental, parking and gas, and eating whenever/wherever we wanted, we spent about $1,500 less than we would have spent for 2 moderate rooms on-site...and getting an on-site suite was even worse.
The boys having their own room was huge at night and in the morning. At night we (the adults) could sit in the living room, have a beverage, watch TV and talk, surf the 'net for attractions we hadn't thought of, all without waking the boys. (This paid off directly when we discovered that the shuttle was scheduled for a rare night launch while we were ther. We simply adjusted the schedule and my kids got to see something they might not see again.)
At the CR, even washing your hands in the middle of the night might wake someone.
In the morning, everyone got up at their own time. And one child getting up and going downstairs to have breakfast with grandma and grandpa didn't wake the other. They had choices for breakfast - cereal and fruit, frozen waffles ('cause you have a toaster), eggs ('cause you have a stove, pan, spatula and plates), etc. And nobody ever ate anything sitting on a bed.
At the Caribbean, we kept some fruit in our room but usually I walked across the resort to the food court to bring stuff back.
Full kitchen and Publix nearby allowed us to stock a variety of stuff for those times we just wanted a snack or sandwich.
The laundry was nice because we packed way less clothing, and there is not much I look forward to less than putting on cold, damp trunks that didn't dry in my room while I was at the park. This allowed us to check the kids' car seats on the flight without paying for extra bags. To be fair, at CR the coin laundry was close to our room but someone had to attend to it.
Driving to and from parks, parking, all were a breeze. We loaded up just outside our front door (about 3 feet away). At the parks we had to walk a little farther than if we were on the bus, and same was true at end of day. But once the kids were seated in the van, they could sleep until we got to our front door.
At the Caribbean, we walked a lot farther to catch the bus in the morning, waited for the bus going to the correct park, then waited at other stops. At the end of the day, someone would usually give up a seat for my wife and our son. (Thanks to the many of you who did so!) But back at the Caribbean, it was a repeat of the morning. Stopping at numerous stops before getting to ours, then hiking across a
walmart sized parking lot to our room. No question about it, from door to gate and back took much less time by van than bus.
Food. When you're at the park, everyone eats the same things. At the Caribbean, we found that the resort food was about the same thing as in the parks. However, staying off-site, we ate a familar restaurants - Olive Garden, Friday's - and even some fast food. With sensory overload that Disney provides, it was nice for the kids to decompress doing things they would do at home.
And finally, the grounds. Windsor Hills is an immaculate gated community and our townhome was clean, fresh and updated. And our owner was a phone call away. We were fortunate to be just across from the main pool and rec room, and with dozens of happy, spashing kids, I don't know how you do much better. Slides, shooting fountains, and did I mention, lots of kids? If we didn't want to go to the main pool, we had our own screened in spash pool. Used it every day.
Each preceived advantage to staying offsite can be mitigated, but it seems one be hard-pressed to mitigate the totality. I'm sure someday the kids will want the Extra Magic Hours so we'll be back on (maybe for a split).
The irony is that I'd pay more for what I got at Windsor Hills...a lot more. But I paid less...a lot less. Go figure.
). What do you love about staying offsite? What don't you like? How is driving? Should I avoid I-4 at all costs? We're not far from World Drive, which is good, and I think we're going to go to the Walmart for groceries in Kissimmee. Any advice would be FABULOUS! 
