Thanks so much for the replies you guys! I figured Roo must be stronger because all of the dog show leads I've seen for big dogs seem to be made from it. (and it is so much more expensive)
Here is the lead I'm working on now.....as you can see, I'm still experimenting with the best ways to secure the beads (knots, wrapping, etc). This will be mine and not for sale, so I don't mind these little differences and imperfections.
Also, since I haven't finished the handle yet, I haven't rolled it to flatten the stitches. VERY MUCH a work in progress.