Hey Marie, do you know If those really flower in our zone? I would love to pick up a few from cities I've visited, but have always hesitated not trusting the bloom. Do you know much about them?

I looked up several sources and they all said zone 5-9. I think that is marginal. My friend's bloomed once in a while, but I was never sure whether it was the cold or incorrect pruning that was the cause of its non blooming years.
I think it would be worth it 1) if you were willing to wrap/mulch or (2) accept it will be winterkilled sometimes, or (3) if you're willing to get rid of it if it's not bud hardy.

This won't help any of you northerners, but the Citylines bloom like crazy on the cape - I've got quite a few. Of course, I don't bother to prune anything, and it's considerably warmer here, especially in my little back yard.

Mine were all end of season steals at Mahoney's, several years ago, and mostly very small. Now they're pushing 4 or 5 feet tall, and are about as big around - I had thought they were supposed to be compact. Many of them have very deep colored flowers, which is what I was looking for at the time.