Your "home" resort allows you to make reservations 11 months in advance, where you can only make reservations up to 7 months in advance for the others.
If you plan on buying used and plan on going at peak season all the time, I would buy at the resort you really want to stay at.
In my case, I chose to buy new with the incentives they had at the end of last year, and added on with the incentives this year, all for Saratoga Springs. (Bought 200 points, then added on 120).
Personally, I prefer Beach Club and Boardwalk because of their close proximity to Epcot, but I would have had to buy used and it would expire in 2042 verses the expiration of Saratoga Springs of 2054. Since I was spending close to the same amount, I prefer to get the extra 12 years use out of it. If I was "stuck" at Saratoga Springs because of availablity, I would still be happy.
Also, my vacation time is very flexible, so if a particular resort isn't available on certain dates, I have no problem moving my vacation dates around.