Michigan Donut Peaches

We went out plum picking at Jollay's in Michigan this weekend and came across these things:

They're called Donut Peaches or Saturn Peaches.  They (apparently) came from China more than 100 years ago and gained some popularity in the 1990's.  I don't remember ever hearing about them, but seeing them on the tree, they're kind of a novelty.  

Seems like it would be a fun tree to grow in the yard - especially because they're described as 'frost hardy'.