I'd have no problem if this happened. I am a loyal Coke Zero drinker, but it's hard to find it at both resorts. They only have it available at fountains in new or refurbished establishments. And for some stupid reason, only Diet Coke is available in bottles (for the most part).
On the other hand, I love Diet Pepsi, and I know that if they were to switch, I'd have no problem getting it.