You're getting to go well before us! Lucky!
I remembered while reading the posts after mine that our downpayment was just above 1700. There was a giftcard option that you could either take away OR use towards the downpayment, and that was about 800, then we paid 992 on top of that. So it was just about 10% for us.
As
bostontim alluded to, as we financed it we saw it as pre-paying (with a convenience fee).
We were spending the money anyway on trips to DLR, and even though we haven't even been to WDW at all, we just know we will adore it when we go. And although the upcoming 13 months will be interesting, as we pay off our car (2+ years early), make the monthly payments, and save up for the rest of our trip next year December, we know that about a year from then, when the loan is done with, it will all be much easier.

Of course, if we knew we could do *this*, we certainly could have saved up the whole amount, but we didn't know it at the time we bought in! (things have changed massively since March of this year for us, and buying into
DVC has actually been part of the change for the better!)