My favorite is Shenandoah. Gets gorgeous fall color. IME, Heavy Metal is bluest in full sun and very lean growing conditions. Not very familiar with Northwind.

Thanks, gardengal. Of course, I know very little about the soil at my new house--whether it's rich or lean. I liked HM not only because of its color but its height and narrowness/uprightness. But the fall color of Shenandoah is very alluring. Maybe I can use both.

Hoping for some more comments from other gardeners.

I liked mine the first year, but last year they were meh. IIRC, they are "Heavy Metal". Not particularly blue, and they are in full sun. They didn't get very tall and didn't flower well. I think it might be because my soil is too rich, but I'm not sure. They are in full sun, so that's the only thing I can figure out. The turkeyfoot grass growing right next to it was beautiful, go figure.

Sorry but what does IIRC mean?

IIRC = if I recall correctly