As someone pointed out up thread, they aren't guaranteeing the value - they're guaranteeing the % of value / original sales price, which is unlikely to suffer.

As someone pointed out up thread, they aren't guaranteeing the value - they're guaranteeing the % of value / original sales price, which is unlikely to suffer. In other words, if there are huge technology improvements in the S Class, you'd pay for it up front AND in the used car price (sure, the curve might be slightly different, but if anything, may be steeper).