I got a good 40% off bounceback for VWL in September, at a rate better than I paid with an AP discount in 2007 for the same resort and room type.
The AP discounts vary so much. They are very much tied to what type of resort needs to be filled, so you may get 40% at deluxes during the summer when families typically fill the value and mods, or you may get 15% off at mods during snowbird season when the deluxes are busier. There is very little consistency to which resorts get the AP discount and how big the discount is. I remember a few years ago, they offered an AP discount only on the Epcot resorts during the summer. No other deluxes were included.
Your best bet is to check out the AP discount history. I think you'll find your bounceback offer is close to the same, or maybe a little better. I wish they would make the bounceback offers a permanent thing, to reward us loyal visitors.
