I have both. Durandii I've had for probably 5-7 years and Juuli is new last year. In my garden, Juuli is a lighter blue with smaller petals, at least so far. They both do very well under less than ideal conditions. I'd be hard pressed to choose one over the other, but Juuli is new to me, so it's hard to say if she'll look different in another year or so. They're both shortish as clematis goes.

I have both. I prefer Juuli. I do not think a peony is going to be strong enough to hold either one up. I have Juuli growing on a ten year old barberry shrub and she has half killed it. I'm finding this to be a problem with all the integrifolias I planted a few years ago. They are all swamping their shrub partners to death.

Thank you for the tips! I ended up going with Juuli. I had no idea it could grow that tall! I am sure I can find a suitable place to plant it, though.