Back in the early 90's I bought many clematis collections from Wayside at less than what they now charge for one!
Though most "blue" clematises lean more toward the lavender side, they still do give the blue effect, so the plant does interest me since the big box stores around here no longer carry the clematises in bags, like H.F. Young, that were reliable to lend the soft blue look. The only two I've seen this year (out of three stores) was their version of Ville de Lyon, which they call City of Lyon, and Venosa Violacea. I guess the days of Nelly Moser, Jackmanii, Belle of Woking, and other cheap clematises may be over.