I've got about 5 kinds of Clematis but so far two are my favorite, based on their performance this and previous years.
Clematis integrifolia - not a climber, not a huge-bloom-er but nevertheless something I love having in my garden.
And the only one I have managed to germinate seeds from.
Clematis Miss Bateman. Was my first Clematis, planted it close to a pear tree and not I am quite sure some stray vines go all the way to the top branches of the tree.