I second everything Sayhello said. We did our first
ABD this past June and wound up booking our tickets through ABD (via our affiliated TA). I wasn't intending to do this, but it worked out for the best. And she booked the exact seats I wanted for the same price that I would have paid had I booked them myself. The charge for the tickets will show up on your cc as a
Disney Vacations charge (or something like that), not an airline charge. I will be booking our tickets for our 2016 trip the same way.
An interesting note about our trip...the lowest price of the ticket actually coincided closely with our PIF date. I checked ticket prices almost every single day for months and months. There would have been no advantage for us to have booked this far out. I wound up buying the tickets about a week or two before I made the final payment for the trip. The ticket price didn't drop any further after that.