I'm surprised they say that you may get it as a walk-up. I called for it 3 weeks before the date I wanted, only one person, and they were sold out. I even called several times, hoping for a cancellation. I'll try again while I'm at WDW, but I don't have much hope.
We tried to get this last Aug but we couldn't. Even the Poly concierge could not get us in.
This year I book when the dates open last month for May. I think it was around $20-25 (with tax) pp now as I believe I was charged $49 for 2 adults. My dh and I have seen wishes more times than I can count and from so many different perspectives (resorts, restaurant, beaches etc) so we thought this would be a good option. If it was my first or second time seeing wishes I wouldn't want to see it there because of the perspective. that's jmo.