They have soo many dogs. It makes me wonder if they are able to socialize all of them. Also, the prices of the mixed breeds seem a bit high. They cost as much as or more than my Yorkie. If I hadn't wanted a purebred Yorkie, I'd just adopt from a shelter. So many animals need homes, it really doesn't make sense to spend that much on a mixed breed.
But it's ultimately your choice, and if you really love the puppy...