We are making our first trip in late May/June and we were struggling with the onsite/offsite decision. I had made up my mind to stay onsite to be in the 'bubble'. However, once I discovered we could stay in a 3 bed condo at Windsor Hills for 8 nights (which allows 6 parks days plus a rest day) for less than a 7 night stay at a Moderate resort, we booked the condo. It came down to comfort and money. We have two young kids and rest is of the utmost importance. I just didn't think we would have the proper downtown we need sharing a very small room. Plus, Windsor Hills is so close to the Disney property, I don't think we are costing ourselves that much time (maybe a little at MK). It also is a nice feeling that with the money we saved from lodging, we can now do a few extra things for the kids like character meals.
I can guarantee the magic my kids feel will be enhanced simply by a good night's sleep.