You can save EVEN MORE on AP as well by buying the Disney Gift Cards to pay for it. I buy ours at Sam's Club at a "Roughly" 5% discount although they just increased the prices so now it's closer to 4%. However even 4% discount on $779 is another $31 of savings.
Better yet is if you can buy your "Tickets" at a "Discount" (employer discounts,
AAA,
undercover tourist, etc...) and use them ONCE then go to customer service to "Convert" it to an AP, the value of your ticket converts from the "Discounted Price" to the "Gate Price" and THAT value is applied to your AP.
We did this last August. What's better, is that I can get the tickets at a HUGE discount compared to most other sites because my employer (at that time) is a "Preferred" Partner with Disney, and as such they get a HUGE savings, plus it's all through the Disney Site so I was also able to use the Gift Cards to pay for them giving a better discount.
In the end, I probably saved about $350 on 3 Annual Passes (Platinum only)
I also bought the TIW. For us it paid for itself in one trip. I was, however, a bit upset that now you get most of the discounts that you get with TIW, with your AP (a few exceptions) but the TIW "Includes" 18% gratuity where the AP does not. The advantage being that if you don't feel the service was worth the 18% tip, you can tip more appropriately. Still, 20% Discount then add in 18% Tip is still 2% full savings overall (versus no savings)