We stayed at Acadia Estates last May. It's directly opposite Formosa Gardens (where we've stayed many times - check my signature

) which is as close to WDW as you'll get offsite. It
is gated, but, in my experience, the gates are usually open (and that applies to all such communities). There are no amenities on this community, but do you really need them?
Who are you thinking of booking with? As far as I'm aware, most of the properties on Arcadia Estates are managed through All Star Vacations. We booked directly with the owner of one of only a couple of properties (ex-model home)
not managed by them, at half the cost.