Paul grows gorgeous roses, and I'm sure they're all grafted, Andi. Own-root hybrid teas don't even do their best in zone 9, so they'd be a bad investment in lower zones. If you have trouble overwintering them, just buy some of the $5 ones you're seeing and think of them as annuals.
Here's an article by Paul. Look at the photos of his roses. Stunning!
http://garden.org/ideas/view/P...
