Clematis armandii 'Snowdrift'

Today it is rainy and cold, no work given all my jobs are outside jobs. So while running errands I saw the Durham Garden Center and thought I'd stop by to kill some time. I rambled through the beautiful gazing balls and eventually made it out to the nursery.
Stunned I was by the heady aroma of Clematis armandii 'Snowdrift' a plant that I'd never noticed before. You might ask where have I been right? Given this is a early spring bloomer I must have just missed it, the evergreen foliage does look familiar. The blooms are 2 inches and can get to 3 inches.
Being a new plant to me I did a web search on it. I found it was introduced to the west by E.H. Wilson in 1900. The zones it grows in where a bit confusing, I got zones 7-8, 6-10 and 7-10 somebody please make up your mind. I'm in zone 7 so I guess it will do fine here.

Supposedly it will grow in sun/part shade and get as tall as 25 foot. We'll have to think out where this plant will grow as the woody stems should become quite heavy in a matter of a few years. One thought was the corner of out deck under the big white oak to grow with a Carolina Jasmine we want to plant there. The other would be on the back porch where nothing is planted except pansies right now, it could grow onto the 3/4 inch pipe railing and stair, the stair is 4 foot wide. Or should we just build an arbor for it?