I think they're shooting themselves in the foot by not allowing people to order the Kitchen Sink with 2-3 vouchers (though I think it's taking advantage of the program to order a KS with one voucher). We ordered one, and everyone in the place watched as it was delivered to our table -- they immediately had orders for two more just like it.
Remembering how shocked my children were when the giant thing was delivered (I'd ordered it quietly, and they had no clue it was going to be theirs), I would pay cash for the Kitchen Sink -- but only once per vacation! It was one of their favorite things from the entire week.