I have Illustris
I have Illustris. It's currently sleeping for the winter, but once it wakes up, it won't be long until it gets some pups. It produces pups faster than any other EE I've grown, and more of them, too! I'd be glad to share some pups with you if you'd like. Incidentally, I grow mine in pots. If you don't want to dig them up every fall, why not just grow them in pots and bring the pots indoors during the winter? Even if you have a garage that's not completely heated, but sufficiently protected from the elements, that might be good enough to keep it from dying altogether. As long as your garage doesn't get colder than freezing and stays around 40'ish, I bet you could keep it as a perennial like we do and it would just go dormant for the winter.