Hi Ispahan
I've grown Thin Man in zone 4 with no problem for around 7 years...the earliest image I have is from 2007 so it most likely came in 2006. Thin Man has been moved several times, seen temps -30 with and without snow cover and I do not mulch. If they happen to get some leaves blown their way as they fall from the trees they get to keep them through the winter but many of the dl's here get nothing. This is one of my favorite UF's, big, bright and is now planted in the bed against my deck where I can see it bloom without needing to walk down to the main garden. It does seem to multiply a bit slow compared to others , but I don't mind, and it has never been one to slowly dwindle away.
Thin Man 2007
Thin Man 2013
and from the deck looking into the garden 2012
