jb, Vidal is the coarsest of the ice wine grapes. Gewurtztraminer, Riesling, and Cabernet Franc do much better in Niagara and NY. I have tasted virtually all of the ice wines made in Niagara in the last 5 years in my repeated trips. The best ice wines of all are the Rieslings and Scheurebes of Germany. Someone mentioned Austria too a while back, but I've never had an Austrian Ice Wine.
Vidal is heavy and cloying, unidimensional, lacking the necessary acidity and crispness for true balance. It's the reason Vidal is also the cheapest of all ice wine varietals, that and the large supply from prolific vines.